DnD 5e - The Barbarian Handbook

Last Updated: March 29th, 2021

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Disclaimer

RPGBOT uses the color coding scheme which has become common among Pathfinder build handbooks, which is simple to understand and easy to read at a glance.

Red: Bad, useless options, or options which are extremely situational.
Orange: OK options, or useful options that only apply in rare circumstances.
Green: Good options.
Blue: Fantastic options, often essential to the function of your character.

I will not include 3rd-party content, including content from DMs Guild, even if it is my own, because I can't assume that your game will allow 3rd-party content or homebrew. I also won't cover Unearthed Arcana content because it's not finalized, and I can't guarantee that it will be available to you in your games.

The advice offered below is based on the current State of the Character Optimization Meta as of when the article was last updated. Keep in mind that the state of the meta periodically changes as new source materials are released and this article will be updating accordingly as time allows.

Introduction

Barbarians are all about getting angry and dealing damage. They have a ton of hit points, resistance to damage, and Rage gives a wonderful bonus to damage. Barbarians don't get much in the way of skills, so generally they're stuck as combat monsters, but they function equally well as a Defender and a Striker.

After reading this handbook, I encourage you to read my Barbarian Subclasses Breakdown.

Barbarian Class Features

Optional Class Features are detailed below under Optional Class Features.

Hit Points: d12 is the biggest hit die available.

Saves: Strength saves are fairly rare, but Constitution saves are common and typically very problematic.

Proficiencies: Medium armor and martial weapons will get you a long way, but you get no tool proficiencies, and only two skills.

Rage: Rage is the Barbarian's defining class feature. The bonus damage isn't huge, but it's reliable and consistent. The resistance to damage makes Barbarians exceptionally durable. You can rage multiple times in the same encounter if you absolutely need to, but your number of rages per day is limited, so try not to do so if you can avoid it.

Unarmored Defense: This is great flavor for the Barbarian, but won't do much good for you unless your abilities are very high. Your Dexterity and Constitution modifiers need to total +7 to match the total AC bonus provided by half plate armor. That's generally achievable by level 8 unless you rolled for ability scores, and assuming that you started with 14 Dexterity and largely ignored Strength. More realistically, you should expect to hit 20 Constitution by 12th level, and even then Unarmored Defense will only break even with Half plate. If magic armor is an option you'll need to put an ability increase into Dexterity before you have a good reason to drop your armor.

Reckless Attack: Rage makes you resistant to damage from normal weapons (Magical weapons which do weird damage types still work fine), so advantage on attacks against you doesn't matter as much. Go crazy. Kill all of the things.

Danger Sense: In medium armor your dexterity probably isn't fantastic, but advantage on any save is fantastic.

Primal Path: Barbarian subclasses are briefly summarized below. See my Barbarian Subclasses Breakdown for help selecting your subclass.

Ancestral Guardian: Conjure up the spirits of your ancestors to defend yourself and your allies in battle.
Battlerager: Dwarf barbarians who specialize in fighting in spiked armor.
Beast: Manifest teeth, claws, and other fantastic bodily features, and tear your enemies to shreads.
Berserker: Adds the ability to go into a Frenzy while raging, making you even more dangerous at the cost of levels of Fatigue.
Storm Herald: A nature-themed Barbarian, adding features thematically tied to your choice of "Environment", which you can change every time you gain a level.
Totem Warrior: Choose from Animal-themed benefits at several points, allowing you to customzie your barbarian to fill several roles in combat.
Zealot: A great option for reckless players, or for players who tend to die frequently, the Zealot is exceptionally difficult to kill and can be raised from the dead without the expensive material components usually required to do so.
Wild Magic: Throw unpredictable magic into the mix, gaining a randomly-selected buff every time you rage, allowing you to do fantastic things like teleporting in combat.

Extra Attack: Two attacks means potentially twice as much damage in a turn, and twice as much opportunity to apply your rage bonus to damage.

Fast Movement: Amusing, but not game-changing.

Feral Instinct: You are basically immune to surprise attacks. Advantage on initiative will allow you to go first frequently, so be sure to get into position to keep enemies from reaching your squishy allies.

Brutal Critical: Critical hits are very rare, and this makes it difficult to use a Maul effectively.

Relentless Rage: This will keep you conscious for a long time if you get hit with a low numbers of high-damage attacks, but lots of small attacks will raise the DC too quickly for this to remain effective. Be sure to eliminate weak but numerous enemies before your HP starts getting scary.

Persistent Rage: There are very few effects which can end your rage prematurely without knocking you onconscious.

Indomitable Might: By now you might very easily have 20 Strength, so you're guaranteed to get a ridiculously high roll on any Strength check. Remember that saves and attacks aren't checks, so you still need to roll high on those.

Primal Champion: The equivalent of 4 ability increases all at once. Your abilities should be absurd by this point, so now may be a good time to abandon your armor in face of running around slaying monsters in your undergarments.

Optional Class Features

Introduced in Tasha's Cauldron of Everyting, Optional Class Features offer ways to add additional features or replace existing ones. These rules are optional, and you should not assume that your DM will allow these features without consulting them first.

Assessments and suggestions for specific Optional Class Features are presented here, but for more information on handling Optional Class Features in general, see my Practical Guide to Optional Class Features.

Primal Knowledge (Addition): The Barbarian is notoriously useless outside of combat because their class features are almost exclusively dedicated to acts of violence. The one tiny sliver of non-combat functionality which they get is their skills, and while they get the standard 2 class skills their skill options are often only situationally useful so most barbarians are locked into Athletics and Perception because those are the only consistently useful choices. Adding 2 more skill proficiencies does a lot to improve the Barbarian's non-combat capabilities, and granting them past level 1 means that the barbarian can grow and develop as a character, learning new skills in addition to new and exciting ways to hurt stuff.

I recommend granting Primal Knowledge to all characters who take barbarian as their primary class and whose race doesn't provide additional skill proficiencies. Even for races which do provide skill proficiencies, it's probably still a good choice to grant this but consider how your player feels about their character's capabilities outside of combat before you make a decision.

I recommend considering it on a case-by-case basis for class dips. Most multiclassed barbarians will go to level 3 to get Reckless Attack, and the additional skill may an unneeded benefit for what may already be a very powerful character.

Instinctive Pounce (Addition): At this level the Barbarian has Fast Movement, so many barbarians will have either 35 ft. or 40 ft. speed. Moving half of that speed when you begin a rage allows the Barbarian to get into melee faster, which is essential since the Barbarian is essentially a melee-only class.

I recommend allowing Instinctive Pounce on all barbarians whose subclasses don't add a complicated secondary effect when they rage (such as the Path of Wild Magic's roll on the Wild Magic Table). The amount of extra movement isn't going to break the game and it won't be helpful in every fight, but it makes the Bonus Action to Rage feel less like a tax and more like an actual tactical decision point. It also allows the DM to set encounters in larger areas without accidently punishing the Barbarian, thereby offering the DM more options for encounter design.

Ability Scores

Barbarians are all about their physical ability scores. If your scores are good enough you can forgo armor, so it's nice to have adequate Dexterity and Constitution to beat the AC bonus provided by half plate.

Str: Barbarians are all about lots of Strength and big weapons, so Strength should almost always be your best ability.

Dex: 14 Dexterity is great to boost your AC with half plate. If you prefer to go armor-less, look for an item to boost your Dexterity so that you can spend your ability increases on Strength and Constitution.

Con: Second only to Strength. Barbarians take a lot of damage, so you need all the hit points you can get. Constituion also powers Unarmored Defense.

Int: Dump stat. Intelligence saves are very rare, and Barbarians don't get any Intelligence-based skills.

Wis: Wisdom saves are common, so don't dump it, but don't put a ton of effort into improving it.

Cha: Charisma only matters for a couple of the Barbarian's skills, and for the Berserker's Intimidating Presence. If you went for Totem Warrior and didn't pick up Intimidation, you can dump Charisma and use the points to boost your Wisdom.

Point Buy	Standard Array
Str: 15 Dex: 14 Con: 14 Int: 8 Wis: 10 Cha: 10	Str: 15 Dex: 13 Con: 14 Int: 8 Wis: 12 Cha: 10

Races

Look for bonuses to Strength and medium size so that you can effectively use big weapons like a Greataxe. Bonuses to Constitution are also important since the Barbarian's AC is typically much worse than that of other front-line Defenders like the Fighter or the Paladin, and Reckless Attack compounds that challenge. Even with damage resistances from rage, you still need those extra hit points.

Beyond ability score increases and size, look for traits which solve problems for the Barbarian. Damage resistances are great, move speed is nice, and other traits which complement the Barbarian's usual tactics can be very helpful. Darkvision is great since the Barbarian can't cast spells to get it. Avoid things like innate spellcasting (you can't cast spells which raging), and be careful when consider active abilities which require your Bonus Action since they'll be difficult to use in the same encounter as Rage.

Note that setting-specific races like the Changeling and the Satyr are addressed in setting-specific sections, below.

Aarakocra^EEPC

Customized Origin: Flight is great, and even if you never get far off the ground the Aarakocra's 50-foot speed is excellent for getting into melee quickly, and Fast Movement will raise it to 60 feet. However, flight speed and ability increases are all that the Aarakocra offers, and flight is less tactically-impactful for the Barbarian than for other classes since the Barbarian is so locked into melee. You're also limited to light armor, so you'll likely want to rely on Unarmored Defense, which won't match medium armor until you're high level and have spent numerous Ability Score Increases.

Default Rules: Flight is fantastic, but the Aarakocra's abilities don't work well for a Barbarian.

Aasimar^VGtM

Customized Origin: +2/+1 increases (each subrace offers a +1 increase), two damage resistances, Darkvision, and Healing Hands will help you maintain your big pile of hit points despite comparably low AC.

Fallen: A great crowd control option for a class which has very few of them. The Frightened condition imposes Disadvantage on attacks, offsetting Reckless Attack and putting you at a tactical advantage.
Protector: Flight for one minuute once per day may be enough to solve your flight-based needs in most scenarios, and the damage boost is always helpful.
Scourge: Scourge's transformation hurts you, but you have plenty of hit points to burn. What the Barbarian doesn't have is a way to handle crowds, which Scourge's transformation addresses farily well.

Default Rules: Two damage resistances, Darkvision, and Healing Hands will help you maintain your big pile of hit points despite comparably low AC.

Fallen: A +1 Strength increase is enough to scrape by, and Necrotic Shroud is a powerful crowd control effect which helps the Barbarian handle crowds of enemies.
Protector: Access to flight is tempting, but you can get that from other places.
Scourge: Interesting, but you need a Strength bonus more than a Constitution bonus.

Aasimar (DMG Variant)^DMG

Customized Origin: +2/+1 increases, Darkvision, and two damage resistances. That's a fine base, and the innate spellcasting may be somewhat helpful for the Barbarian since their healing options don't go beyond hit dice and they can't produce light without an item.

Default Rules: Bad ability spread.

Bugbear^VGtM

Customized Origin: +2 Str, +1 Con, Darkvision, and one skill. Long-limbed may not be as useful for the Barbarian as it is for some other classes because hit-and-run tactics generally don't make sense for the Barbarian, but if you can make it work you may be able to offset the drawback of Reckless Attack by remaining far enough away that enemies can't attack you. Surprise Attack is hard to use unless you invest enough in Dexterity that you can easily surprise your enemies.

Default Rules: Dexterity might not seem like an obvious benefit for a barbarian, and it's not as good as Constitution, but the AC bonus is still helpful. Reach makes it easy to compete with larger creatures or attack smaller foes at a distance, and Sneaky allows you to be an ambush predator.

Custom Lineage^TCoE

Customized Origin: The Customizing Your Origin rules make no change to the Custom Lineage.

Default Rules: +2 Strength and a feat. Personally I prefer the Variant Human because 16 Str and 16 Con is better at low levels than 17 Str and 15 Con, but Darkvision is really tempting so I won't blame you for choosing the Custom Lineage over the Variant Human.

Dragonborn^PHB

The Draconblood and Ravenite subraces are addressed under Races of Wildemount, below.

Customized Origin: +2 Str, +1 Con, damage resistance, and a breath weapon. The Dragonborn's breath weapon is helpful for handling groups of weak enemies which a Barbarian would normally need to wade through one or two at a time.

Default Rules: A bonus to Strength is great, but the bonus to Charisma is wasted unless you want to use Intimidating Rage a bunch. The Dragonborn's breath weapon is helpful for handling groups of weak enemies which a Barbarian would normally need to wade through one or two at a time.

Dwarf^PHB

Customized Origin: +2 Str and each subrace will provide a second increase. Darkvision is great, and resistance to poison will mitigate one of the most common types of damage which Rage doesn't give you resistance to by default. The weapon proficiencies are redundant, so trade for 4 tool proficiencies. The Dwarven Fortitude racial feat can be a great way to keep yourself alive in combat if your AC is low and you don't have healing readily available.

Duergar^SCAG: Sunlight Sensitivity is a huge problem, but otherwise this is a fine option. Duergar Resilience provides resistance against two very common status conditions which can easily take the Barbarian out of a fight, and while the innate spellcasting won't work while raging it gives you other options to solve problems.
Hill^PHB: +1 con and even more hit points on top of it. Not super exciting, but very functional.
Mountain^PHB: +2 con, and trade the armor proficiencies for two more tool proficiencies.

Default Rules: The Constitution bonus is great and Darkvision is always welcome. The Dwarven Fortitude racial feat can be a great way to keep yourself alive in combat if your AC is low and you don't have healing readily available.

Duergar^SCAG: In a subterranean campaign, this is at least on par with Mountain Dwarf. Otherwise, Sunlight Sensitivity is a huge problem.
Hill^PHB: A bonus to wisdom is nice, but not going to make a big difference. The bonus hit points is also helpful, but you already have a d12 hit die and a Constitution bonus from the general Dwarf traits. Hill Dwarf is fine, but it feels silly to choose Hill Dwarf over Mountain Dwarf.
Mountain^PHB: A bonus to Strength on top of the Dwarf's bonus to Constitution is perfect for the Barbarian. Two +2 increases means that you can start with two 17's at first level, and can reach 20 Strength and 20 Constitution at level 12. This leaves more room to raise your Dexterity or to pick up feats without sacrificing exceptionally high Constitution.

Elf^PHB

The Palid Elf subrace is addressed under Races of Wildemount, below.

Customized Origin: +2 Str, Darkvision, one skill. Fey Ancestry protects you against effects which normally work very well to take barbarians out of a fight due to poor Wisdom saving throws. Each subrace provides a second ability score increase, and many provide weapon proficiencies which you can trade for tool proficiencies.

Drow^PHB: Sunlight Sensitivity is a pain, and the innate spellcasting doesn't work while you're raging so it's minimally useful.
Eladrin^MToF: Fey Step works while raging, but all of the secondary effects are Charisma-based, which limits their effectiveness. You'll likeky have better results with the Shadar-Kai.
Eladrin (Variant)^DMG: Because you actually cast a spell, Misty Step won't work while raging. The weapon proficiencies are useless, so trade them for tool proficiencies. At that poit, the regular Eladrin is a better choice.
High Elf^PHB: An Intelligence-based cantrip is nearly useless for the Barbarian.
Sea Elf^{EGtW / MToF}: Maybe an option in an aquatic campaign, but even then Path of the Beast allows you to adapt to breath and fight underwater so this isn't totally necessary.
Shadar-Kai^MToF: Resistance to necrotic damage and teleportation. Great for a class with few movement options beyond running, and Blessing of the Raven queen provides better damage resistance than Rage does.
Wood Elf^PHB: A little bit of extra speed, weapon proficiencies which you'll trade for tool proficiencies, and Mask of the Wild. It works fine, but you don't get anything that makes you a better barbarian.

Default Rules: A bonus to Dexterity isn't as helpful as one to Strength or Constitution, but the Elf's other racial traits are great for the Barbarian. Darkvision is excellent, and Keen Senses saves you a skill choice.

Drow^PHB: Nothing helpful for the Barbarian.
Eladrin^MToF: Fey Step is really good, but that's the only appeal.
Eladrin (Variant)^DMG: Misty Step can't be cast while raging.
High Elf^PHB: Nothing helpful for the Barbarian.
Sea Elf^MToF: +1 Constitution is the only thing you need from the Sea Elf.
Shadar-Kai^MToF: Dexterity and Constitution isn't ideal for a barbarian, but your AC will be really good, and you get a damage resistance and the ability to teleport.
Wood Elf^PHB: A wisdom bonus might help with your Wisdom saving throw, but that's about it.

Firbolg^VGtM

Customized Origin: +2 Str, +1 Con. Firbolg Magic is hard for the Barbarian to use, and while Hidden Step works while raging it's rarely a good choice because you should be on the front lines drawing fire and shrugging off damage. Speech of beast and leaf is neat, but most barbarians dump Charisma.

Default Rules: A bit too tricksy and indirect for a Barbarian.

Genasi^EEPC

Customized Origin: +2 Str is a fine start, and each subrace will provide a second increase which you can put into Con.

Air: Levitate isn't helpful for a class that's almost entirely melee-only.
Earth: Earth walk is neat and Merge With Stone suddenly makes you very good at stealth, but those effects are only situationally useful, so you're mostly leaning on the same +2/+1 increases that nearly every race gets.
Fire: Fire resistance and Darkvision are great, but if that's all that you want the Tiefling will do fine. The Fire Genasi's Innate Spellcasting is Constitution-based, making it a viable for the Barbarian. You may even find that Produce Flame offers an effective option for attacking at range.
Water: The spells are excellent utilities. Resistance to Acid is nice, but situational. I would probably only go this route in an aquatic campaign, but it's not as useless on land as options the Sea Elf.

Default Rules: Bonus Constitution isn't as good as Strength, but it boosts the Barbarian's AC (provided that you're unarmored) and hit points, both of which are important.

Air: Dexterity isn't particularly important for Barbarians, and the ability to hold your breath is extremely situational.
Earth: Bonus Strength, and the ability to move across difficult terrain unimpeded helps you to get into melee in situations where it's normally difficult to do so.
Fire: Intelligence is for Wizards. The resistance to fire is tempting, and Produce Flame is a decent option, but the spells don't really play to the Barbarian's strengths.
Water: Wisdom is a good defensive ability, and the spells are excellent utilities. Resistance to Acid is nice, but situational.

Gith^MToF

Customized Origin: A base +1 increas, and each subrace provides a +2, so you can hit +2 Str and +1 Con.

Githyanki: One skill and some armor and weapon proficiencies which you can trade for a total of 5 tool proficiencies. The innate spellcasting offers some utility options, including teleportation via Misty Step, but they'll be totally useless while raging.
Githzerai: Mental Discipline will protect you from common status conditions which are frequent problems for the Barbarian, but the Githzerai's innate spellcasting may be less useful for the Barbarian than the Githyanki's, and the Githzerai does nothin to expand your capabilities outside of combat like the Githyanki does.

Default Rules: Githyanki are great, Githzerai are terrible and you should ignore them.

Githyanki^MToF: +2 Strength, some extra proficiencies, and Giyhtanki Psionics gives you some magic options to overcome problems that many barbarians can't handle.
Githzerai^MToF: Nothing helpful for Barbarians.

Gnome^PHB

Customized Origin: +2/+1 increases () Small size can be hard, but you can get by with a longsword in two hands or by using Path of the Beast and fighting with teeth and claws. Darkvision is always nice, and Gnome Cunning will protect you from magic effects which are a serious problem for most barbarians.

Deep (Svirfneblin)^{EEPC / SCAG}: Superior Darkvision without the usual limitation of Sunlight Sensitivity, and Stone Camouflage helps with stealth in some cases. Neither are especially useful for the Barbarian since barbarians don't fight at range and generally the Barbarian isn't built for stealth.
Forest^PHB: Natural Illusion and Speak with Small Beasts are weird choices for the Barbarian, but Minor Illusion can do a lot before your spell save DC actually matters so you may be able to use it to great effect outside of combat.
Rock^PHB: Nothing useful. Tinker is a fun novelty, but it doesn't actually make your character better

Default Rules: Nothing helpful for the Barbarian.

Deep (Svirfneblin)^{EEPC / SCAG}: Dexterity and stealth abilities aren't useful for Barbarians.
Forest^PHB: Nothing helpful for the Barbarian.
Rock^PHB: The constitution bonus helps, but it's not nearly enough to make the Gnome viable for a Barbarian.

Goblin^VGtM

Customized Origin: +2 Str, +1 Con, and Darkvision. Fury of the Small is a decent damage boost, and Nimble Escape makes hit-and-run tactics possible, but those don't add much to the Barbarian.

Default Rules: Nothing helpful for the Barbarian.

Goliath^EEPC

Customized Origin: +2 Str, +1 Con, one skill, and damage resistance to cold. Stone's Endurance adds the Barbarian's already impressive ability to withstand damage. A great package, and very simple to build and play successfully.

Default Rules: Tailor-made to be a melee monster. Bonuses to your important abilities, free Athletics proficiency, and Stone's Endurance adds a pile to your effective daily hit point total.

Half-Elf^PHB

Customized Origin: +2 Str, +1 Con, +1 anything else (I recommend Dex or Wis), Darkvision, and Fey Ancestry will help with charm effects.

Aquatic Half-Elf^SCAG: Only in an aquatic campaign.
Drow Half-Elf^SCAG: Innate spellcasting is hard for the Barbarian to use, especially combat options like Faerie Fire.
High Half-Elf^SCAG: Tool proficiencies can be helpful, especially crucial options like Thieves' Tools, but I would take two skills over four tools every time. The cantrip is nearly unusable unless you go for a utility option, but in that case I would still rather have two skills.
Standard Half-Elf^PHB: To skills. Always useful.
Wood Half-Elf^SCAG: Nothing as good as two skills.

Default Rules: Several of the half-elf variants are good choices, and if you want to excel at Intimidation half-elf is the way to go. Otherwise, the Mountain Dwarf and Variant Human will be better at killing things.

Aquatic Half-Elf^SCAG: Only if you're in an aquatic campaign.
Drow Half-Elf^SCAG: The spells are decent, and Faerie Fire presents a way to handle invisible foes which Barbarians normally can't handle, but you'll have trouble using Dancing Lights and Darkness, and you can't cast spells while ragin.
High Half-Elf^SCAG: Weapon training is redundant, and Barbarians won't get much use out of a cantrip. You might consider Booming Blade or Green-Flame Blade, but you'll have better damage output from relying on conventional attacks and you can't cast spells while raging.
Standard Half-Elf^PHB: Two skills can get you quite a lot. Coupled with the Half-elf Charisma bonus you could easily be your party's Face.
Wood Half-Elf^SCAG: Weapon training is redundant and Mask of the Wild won't be useful without Stealth proficiency, but Fleet of Foot is great if you want to be fast.

Half-Orc^PHB

Customized Origin: With the exception of possibly changing the racial skill, the Half-Orc is already a perfect barbarian. Even with customized origins, Relentless Endurance and Savage Attacks synergize very effectively with the Barbarian's existing features.

Default Rules: The Half-Orc is tailor-made for the Barbarian. Bonuses to Strength and Constitution are essential, Darkvision is great, and you save a skill choice on Intimidate. The Half-Orc's other abilities match some of the Barbarian's class features, but it appears that they work together, so you can essentially double-down on Brutal Critical and Relentless Rage. The Prodigy racial feat is excellent if you plan to use Athletics for grappling. The Orcish fury racial feat is tempting with a greataxe, but probably not worth the feat.

Halfling^PHB

Customized Origin: +2 Str, Brave helps against common fear effects, and Lucky is good on literally any character. Subraces provides a second increase which can go into Con. Small size is a hindrance because it limits your weapon options, but you can get by on using a longsword two-handed.

Ghostwise^SCAG: Silent Speech is a hard choice since most barbarians dump Charisma.
Lightfoot^PHB: You should not be hiding behind people. The Barbarian is the class that everyone else hides behind.
Stout^PHB: Poison resistance protects you from one of the most common damage types which Rage doesn't already protect you against.

Default Rules: A dexterity bonus is okay for Barbarians, but small size is a hindrance because you can't use big weapons like a Greataxe, and without a Strength bonus you're at an even larger disadvantage compared to other races.

Ghostwise^SCAG: Nothing helpful for the Barbarian.
Lightfoot^PHB: Nothing helpful for the Barbarian.
Stout^PHB: A small Constitution bonus, and resistance to poison. Like a small dwarf.

Hobgoblin^VGtM

Customized Origin: +2 Str, +1 Con, Darkvision, and some proficiencies which you can trade for tools. Saving Face is great for saving throws, and if you have enough allies nearby the bonus can make up for the Barbarian's weak mental saves.

Default Rules: The Consitution bonus and Saving Face are both great, but that's really the only thing that the barbarian can use.

Human

Customized Origin:

Standard: With perfect ability scores on the table for every race, there is no reason to play the Standard Human.
Variant: The Customizing Your Origin rules make no change to the Variant Human.

Default Rules: Versatile and fantastic at everything. The Prodigy racial feat is excellent if you plan to use Athletics for grappling.

Standard: Barbarians really only need two ability scores, but a +1 to all of your scores can be helpful if you use the point buy ability generation method to give yourself low, odd-numbered base abilities to save points or if you want to start with 16 Str, 16 Dex, and 16 Con.
Variant: You still get crucial bonuses to your Strength and Constitution, and you can get an awesome feat at level 1. Great Weapon Master seems like an obvious choice, but remember that at low level a -5 penalty to your attacks is crippling, so you may want to save it for higher levels when you can more easily handle that penalty. The bonus skill is nice, but not essential.

Kenku^VGtM

Customized Origin: +2 Str, +1 Con, two skills. That's really everything that the Barbarian benefits from.

Default Rules: Nothing helpful for the Barbarian.

Kobold^VGtM

Customized Origin: +2 Con, Darkvision, and Grovel, Cower, and Beg. You play a kobold for Pack Tactics, and Pack Tactics is much less appealing since you have Reckless Attack.

Default Rules: Pack Tactics is redundant with Reckless Attack, and if you want need Pack Tactics there is basically no mechanical reason to play a kobold.

Lizardfolk^VGtM

Customized Origin: +2 Str, +1 Con, two skills, and Hungry Jaws. Natural Armor is mostly redundant with Unarmored Defense, and you'll almost never use Bite except when you're using Hungry Jaws. Cunning Artisan and Hold Breath are neat, but rarely impactful. That makes Hungry Jaws the big draw here, and at once per Short or Long Rest, it's good but not fantastic.

Default Rules: Natural Armor and the lizardfolk's Constitution increase conflict a bit on a barbarian because Unarmored Defense and Natural Armor both provide alternatives to conventional armor, but the lizardfolk still makes a fun barbarian.

Locathah^LR

Customized Origin: +2 Str, +1 Con, two skills, and an impressive list of condition resistances which will help keep you in a fight when special abilities are being thrown around. Limited Amphibiousness is a bit of a pain, but you can solve that with a sufficiently large bathtub or barrel dragged around in a cart or wagon.

Default Rules: Similar to the Bugbear in terms of ability increases, but not quite as useful. The natural armor is wasted unless you have less than 14 Consitution, which is a terrible idea. Leviathan Will offers some helpful defenses against status effects, and two additional skills will make you more capable outside of combat.

Orc^VGtM

Note that errata has corrected the multiple versions of the Orc to all provide the same traits. The Intelligence decrease has been removed, and the Primal Intuition now allows selecting two skills from a list. The Orc of Exandria entry from Explorer's Guide to Wildemount omits the Powerful Build trait, but it's not clear if that was an intentional change.

Customized Origin: The Customizing Your Origins rules doesn't change the Orc much for the Barbarian. The ability score increases still work great, but you might choose to take skills not on the race's list of options. Regardless, the Half-orc is still probably a fit for the Barbarian.

Default Rules: Aggressive is cool, but the half-orc is considerably better than the full orc.

Tabaxi^VGtM

Customized Origin: +2 Dex, +1 Con, Darkvision, two skills. The signature feature is Feline Agility, which works fine with Fast Movement but it doesn't solve any problems that you couldn't solve by dashing occasionally.

Default Rules: Nothing helpful for the Barbarian.

Tiefling^PHB

Customized Origin: +2 Str, +1 Con, Darkvision, and fire resistance. Most subraces/variants offer innate spellcasting of some kind. The innate spellcasting is Charisma-based, so anything which requires an attack or a save is largely worthless, and since you can't use it while raging it's even harder to use. If you really want something similar, consider the Fire Genasi if you can't find a tiefling with worthwhile spellcasting.

Asmodeus^PHB/MToF: Bad spellcasting options for the Barbarian. Hellish Rebuke is the best part, but you can't use it while raging so it's still a really hard option for the Barbarian to use effectively.
Baalzebul^MToF: Bad spellcasting options for the Barbarian.
Dispater^MToF: None of the spellcasting is offensive, but it's all situationally useful utility options which may be hard to use effectively.
Fierna^MToF: Bad spellcasting options for the Barbarian.
Glasya^MToF: Not typically in the Barbarian's wheelhouse, but minor illusion can do a lot before you save DC matters and Invisibility doesn't care about save DC at all.
Levistus^MToF: Ray of Frost is offensive, Armor of Agathys will break immediately, and you can't fight in magical darkness.
Mammon^MToF: Utility options which you might be able to use out of combat
Mephistopheles^MToF: Mage Hand is probably the best part.
Zariel^MToF: All offensive options which will conflict with Rage.
Variant: Feral^SCAG: The Customizing Your Origin optional rules make the Feral variant obsolete. All it does is rearrange your ability score increases.
Variant: Devil's Tongue^SCAG: Bad spellcasting options for the Barbarian.
Variant: Hellfire^SCAG: Hellish Rebuke is better for the Barbarian than Burning Hands, so we went from a bad option to a worse option.
Variant: Winged^SCAG: Innate spellcasting is hard, but flight is great. The Winged Tiefling is a better and more interesting option than the Aarakocra. You still have issues with flight being less useful when you're locked into melee, but unlike the Aarakocra flight isn't the race's only interesting racial trait since you still get Darkvision and fire resistance, and you also get to stay in medium armor so your AC will be better.

Default Rules: Nothing helpful for the Barbarian.

Asmodeus^{PHB / MToF}: Nothing helpful for Barbarians.
Baalzebul^MToF: Nothing helpful for Barbarians.
Dispater^MToF: Nothing helpful for Barbarians.
Fierna^MToF: Nothing helpful for Barbarians.
Glasya^MToF: Nothing helpful for Barbarians.
Levistus^MToF: Nothing helpful for Barbarians.
Mammon^MToF: Nothing helpful for Barbarians.
Mephistopheles^MToF: Nothing helpful for Barbarians.
Zariel^MToF: Legacy of Avernus has some neat spells, and the Strength increase is nice, but that's not enough to make this a useful option.
Variant: Feral^SCAG: Bad ability spread.
Variant: Devil's Tongue^SCAG: Nothing helpful for Barbarians.
Variant: Hellfire^SCAG: Nothing helpful for Barbarians.
Variant: Winged^SCAG: Flight doesn't fix the ability score mismatch.

Tortle^TP

Customized Origin: +2 Str, +1 Con, one skill, and fixed 17 AC without a shield so you can dump Dexterity to 8 and not worry about it (except for Dexterity saves, which are common). Hold Breath and Shell Defense are neat but won't see much use, so the big appeal of the Tortle is being able to dump Dexterity without sacrificing AC compared to medium armor. That will free up points to start with higher mental ability scores, which can help a great deal with skills.

Default Rules: +2 Strength and 17 natural armor is fantastic for a Barbarian. With a solid source of AC, you don't need to worry about Dexterity, especially at low levels before you've picked up multiple Ability Score Increases. Survival proficiency is nice, too.

Triton^VGtM

Customized Origin: +1 to three ability scores, Darkvision, cold resistance. The innate spellcasting offers some situational utility options. Emmisary of the Sea is hard since most barbarians dump Charisma. Still, this is one of the most functional and interesting of the aquatic race options for a non-aquatic campaign.

Default Rules: The ability increases are decent, but the triton's other racial traits don't do much for the barbarian.

Verdan^AcInc

Customized Origin: +2 Str, +1 Con, one skill. Telepathic Insight isn't quite as good as the Gnome's Cunning, but it's still good, and Intelligence saves are fairly rare. Black Blood Healing is neat, but on a d12 hit die it's not reliable. The weird size mechanic is annoying since the Barbarian typically depends on using big weapons. Telepathic Insight is a helpful mental defense against saves which the Barbarian typically has trouble with, but you're going to struggle offensively.

Default Rules: +1 Constitution is not enough, and Black Blood Healing is less effective with larger hit dice.

Yuan-Ti Pureblood^VGtM

Customized Origin: +2 Str, +1 Con, Darkvision, poison immunity, and Magic Resistance protects you from one of the Barbarian's biggest and most problematic weaknesses. The innate spellcasting is useless, but honestly it doesn't matter because everything else is so good.

Default Rules: Magic Resistance is great, but not nearly enough.

Setting-specific races are address below. Not every setting allows every race, and while most races presented in the core rules and in content for the Forgotten Realms can be used in other settings, races specific to settings like Ravnica aren't typically allowed in other settings. Talk to your DM about what races are allowed in your game.

Races of Eberron

Bugbear^ERLW: See above under the general Races section.

Changeling^ERLW

Customized Origin: +2 Str, +1 Con, two skills, and Shapechanger. Shapechanger doesn't fit well with the Barbarian's play style, so there is basically no mechanical reason to play a changeling barbarian. The ability score increases and skills are obviously fine, but there are numerous other races that provide those benefits and also traits which help the Barbarian.

Default Rules: Bad ability spread.

Goblin^ERLW: See above under the general Races section.

Hobgoblin^ERLW: See above under the general Races section.

Orc^ERLW: See above under the general Races section.

Kalashtar^ERLW

Customized Origin: +2 Str, +1 Con, and some interesting mental defenses. Resistance on all Wisdom saving throws is really appealing for the Barbarian, protecting you from most charm and fear effects, as well as countless spells and other more unique abilities. Resistance to psychic damage is appealing for the bear totem barbarian because you can get resistance to all damage types while raging.

Default Rules: Bad ability spread. Resistance to psychic damage is neat because it means that a bear totem barbarian can be resistant to all damage, but that is not enough to make this a good choice.

Shifter^ERLW

Customized Origin: Each subrace will give you a +2 increase (put it into Str), a +1 increase (put it into Con, generally), Darkvision, and one skill. You also get Shifting, which is the Shifter's signature feature. It's a decent combat buff on its own, and your subrace will offer additional effects.

Beasthide: A bigger pool of temporary hit points and a modest AC bonus do a lot to complement the Barbarian's already impressive durability.
Longtooth: Many barbarian subclasses don't lean heavily on their Bonus Action once Rage is running, so adding the ability to make a bite attack with your Bonus Action is a significant increase to your damage output. Unfortunately, you'll need to spend two Bonus Actions at the beginning of combat to get the Rage+Bite combo going, but in long combats or if you have a couple turns to prepare before combat you can be very effective.
Swiftstride: The intent of this ability is to let you move away from enemies when they get into melee with you so that you don't need to Disengage on your turn. Barbarians want to get into melee as fast as possible and stay there.
Wildhunt: Negate the Advantage on attacks against you granted by Reckless Attack. That alone is mathematically much better protection than the extra temporary hit points and the AC bonus from Beasthide.

Default Rules: Darkvision is great, and some of the Shifter options work for the barbarian conceptually, but you may have trouble combining Shifting and Rage since both are activated as a Bonus Action. At low levels Shifting can provide a useful alternative while your number of Rages is small, and even once you can comfortably rage during every fight you may find that in some situations it helps to use Shifting before you use Rage so that your Temporary Hit Points can absorb some damage while you get yourself up and running.

Beasthide: Perfect ability score increases, proficiency in an important skill, extra Temporary Hit Points, and you get +1 to AC while shifting so you're even more durable.
Longtooth: While Dexterity isn't quite as nice as Constitution, it's still somehwat helpful. Intimidation isn't a good skill for the barbarian, but that's not the draw here. The ability to bite as a bonus action means that you get as many attacks a chatacter using two-weapon fighting without giving up a shield or a two-handed weapon. Extra attacks means more opportunities to apply your growing damage bonus from Rage.
Swiftstride: Bad ability spread.
Wildhunt: Bad ability spread. The Wildhunt Shifting Benefit can temporarily offset the drawback of Reckless Attack, but you don't get to use Shifting frequently enough to make this a good option in the face of the lack of a Strength bonus.

Warforged^ERLW

Customized Origin: The Customizing Your Origin rules make no meaningful changes to the Warforged. You can move the Constitution increase around, but increasing Constitution is still the best way to use that increase.

Default Rules: Increase Constitution, a flexible increase which goes into Strength, +1 AC, some resistances and immunities, and no need to sleep. A great formula for a simple, durable barbarian. Be sure to pick up proficiency in Perception to capitalize on the fact that you don't need sleep so that you can remain alert and watch over your party during long rests.

Dragonmarks

While the design intent for Dragonmarks was that they would offer some innate spellcasting for everyone, every dragonmark includes an expanded spell list which is arguably a more significant benefit than most of the provided racial traits. Because the expanded spell options are such an important part of the dragonmarks, if you're not playing a spellcaster you're giving up a huge part of your racial traits, which makes it exceptionally difficult to justify playing a dragonmark character who can't cast spells.

Dragonmarked Dwarf^ERLW

Dragonmark traits replace your subrace.

Customized Origin:

Mark of Warding: Warder's intuition offers nothing that the Barbarian is likely to use, and the spellcasting options do nothing useful for the Barbarian.

Default Rules:

Mark of Warding: Bad ability spread.

Dragonmarked Elf^ERLW

Dragonmark traits replace your subrace.

Customized Origin:

Mark of Shadow: Stealth and subtlety aren't typically in the Barbarian's skillset, but the bonus on Dexterity (Stealth) checks helps, and the innate spellcasting offers some magical solutions which you may find useful outside of combat.

Default Rules:

Mark of Shadow: Bad ability spread.

Dragonmarked Gnome^ERLW

Dragonmark traits replace your subrace.

Customized Origin:

Mark of Scribing: The benefits are way too situational to justify, and since most barbarians dump Charisma the communication options aren't helpful.

Default Rules:

Mark of Scribing: Bad ability spread.

Dragonmarked Half-Elf^ERLW

Dragonmark traits replace some of your normal racial traits, as described in the entry for each Dragonmark.

Customized Origin:

Mark of Detection: The bonus to Insight and See Invisibility are the only things which you will find consistently useful. Detect Magic is helpful, but what are you going to do about magic when you find it?
Mark of Storm: Damage resistance is nice, but the innate spellcasting is too situational.

Default Rules:

Mark of Detection: Bad ability spread.
Mark of Storm: Bad ability spread.

Dragonmarked Half-Orc^ERLW

Dragonmark traits replace ALL of your racial traits.

Customized Origin:

Mark of Finding: The theme and the skill bonuses work surprisingly well, but you may find it very difficult to use the innate spellcasting effectively since maintain Concentration on Hunter's Mark is so difficult for the Barbarian.

Default Rules:

Mark of Finding: Bad ability spread.

Dragonmarked Halfling^ERLW

Dragonmark traits replace your subrace.

Customized Origin:

Mark of Healing: The healing provided by the innate spellcasting is extremely minor. Access to Lesser Restoration is nice, but if your party can't provide Lesser Restoration with actual spellcasting you won't be able to make up the difference by casting it once per day.
Mark of Hospitality: None of these features add to the Barbarian's capabilities in any meaningful way.

Default Rules:

Mark of Healing: Bad ability spread.
Mark of Hospitality: Bad ability spread.

Dragonmarked Human^ERLW

Dragonmark traits replace ALL of your normal racial traits.

Customized Origin:

Mark of Finding: See Mark of Finding under Dragonmarked Half-Orc, above. Mechanically, the final racial traits are identical.
Mark of Handling: You don't have the Wisdom to make Animal Friendship reliable, Speak with Animals is only situationally useful, and the skills aren't especially helpful
Mark of Making: Magic Weapon is the only thing that you'll really benefit from, and it's too hard to maintain Concentration to make it viable.
Mark of Passage: A little bit of extra speed and Misty Step once per day. Play an Eldarin or a Shadar-Kai instead.
Mark of Sentinel: A good option for front-line Defender characters like the Barbarian, though without access to spell slots it's not quite as good as it is for spellcasters. Shield is helpful but won't work during Rage, but Sentinel's Intuition helps to make the Barbarian more useful out of combat, and Vigilant Guardian allows you to take a hit for an ally (ideally while you're raging). That's not enough to make this an easy go-to option, but it's definitely playable.

Default Rules:

Mark of Finding: See Mark of Finding under Dragonmarked Half-Orc, above. Mechanically, the final racial traits are identical.
Mark of Handling: A flexible increase means that you can get a crucial Strength increase, but there isn't enough here that's appealing to the Barbarian. If your DM will let you explore training creatures outside of your class features to get things like a griffon mount this might be more useful, but mounts are generally far too frail to be useful in combat, and even if they weren't that's a big assumption to make of your DM.
Mark of Making: Bad ability spread.
Mark of Passage: Strength and Dexterity work fine for the Barbarian, and Magical passage is really useful for a class so totallybereft of magic options, but that's all that we care about and that's simply not enough.
Mark of Sentinel: An interesting possibility for a tanky barbarian focused on defending their allies, but you'll lag offensively by a hug emargin, and this isn't nearly as interesting without the ability to cast spells.

Races of Ravnica

Centaur^GGTR

Customized Origin: +2 Str, +1 Con, one skill, and 40 ft. base speed. The Centaur was already a great choice for the Barbarian, and the Customizing Your Origins rules don't change that. Charge is a great way to open combat, especially if you raged before you moved into melee so that you can spend your Bonus Action on that turn to Hoof someone.

Default Rules: The Strength increase is a great start, and Charge is fantastic on a barbarian. If you rage before charging, the hoof attack is an extra opportunity to apply your Rage bonus to damage, not to mention your crazy Strength bonus.

Goblin^GGTR: See above under the general Races section.

Loxodon^GGTR

Customized Origin: +2 Str, +1 Con, and some more unique traits. Loxodon Serenity protects against very common status conditions can frequently take the Barbarian out of combat due to poor mental saves. Natural Armor is somewhat redundant with Unarmored Defense, but since it's Constitution-based rather than Dexterity-based you could dump Dexterity to 8 and still get as much AC as a barbarian in half-plate. Keen Smell is neat but most Perception checks are based on hearing or sight so you may not find is particularly useful. Trunk is similarly neat, but may not be impactful unless you rely on Grapple and Shove frequently.

Default Rules: The Constitution increase is great, but Natural Armor will hopefully be overridden by Unarmored Defense, and the Loxodon has very little else to contribute to the Barbarian.

Minotaur^GGTR

Customized Origin: +2 Str, +1 Con, one skill. Minotaurs are absolutely perfect barbarians. The ability increases are fantastic. Goring Rush gets you the most important part of the Charger feat, and Hammering Horns gets you the most important part of the Shield Master feat without requiring a shield.

Default Rules: Minotaurs are absolutely perfect barbarians. The ability increases are fantastic. Goring Rush gets you the most important part of the Charger feat, and Hammering Horns gets you the most important part of the Shield Master feat without requiring a shield.

Simic Hybrid^GGTR

Customized Origin: The Customizing Your Origin rules make no meaningful changes to the Simic Hybrid. You can move the Constitution increase around, but increasing Constitution is still the best way to use that increase.

Default Rules: With the flexible ability increase in Strength, the Simic Hybrid is an interesting and versatile option for the Barbarian. The first round of Animal Enhancement gets you some utility options which the Barbarian has no way to replicate, and the second offers several appealing combat options which will nicely complement your class features.

Vedalken^GGTR

Customized Origin: Vedalken Dispassion is a better version of the Gnome's Cunning trait, but beyond that and ability score increases the Vedalken's traits are useless for the Barbarian.

Default Rules: Nothing helpful for the Barbarian.

Races of Theros

Centaur^MOoT: See above under the Races of Ravnica section.

Human^MOoT: See above under the general Races section.

Leonin^MOoT

Customized Origin: +2 Str, +1 Con, Darkvision, one skill. The Leonin's signature trait is Daunting Roar, which provides a powerful crowd-control option that helps the Barbarian handle crowds. Even better: the DC is Constitution-based, and it recharges on a Short or Long Rest so you'll have it available often enough to be impactful.

Default Rules: Leonin make great barbarians for many of the same reasons that half-orcs do, but they trade Relentless Endurance and Savage Attacks for claws, better skills, and the ability to roar and scare enemies.

Minotaur^MOoT: See above under the Ravnica Races section.

Satyr^MOoT

Customized Origin: +2 Str, +1 Con, two skills. Magic Resistance and the Fey creature type will protect you from problematic spells, especially options like Hold Person which may be difficult even with Magic Resistance. Mirthful Leaps may let you jump over small natural hazards like difficult terrain. If you just want durability I would consider the Yuan-Ti Pureblood first, but the Satyr's additional skills offer some utility outside of combat which is very appealing on a class which is already so combat-focused.

Default Rules: Bad ability spread.

Triton^MOoT: See above under the general Races section.

Races of Wildemount

Aarakocra^EGtW: See above under the general Races section.

Aasimar^EGtW: See above under the general Races section.

Bugbear^EGtW: See above under the general Races section.

Dragonborn^PHB

Wildemount presents two new Dragonborn variants, each replacing the standard Dragonborn's ability score increases and damage resistance.

Customized Origin:

Draconblood^EGtW: +2 Str, +1 Con, Darkvision. Forceful Presence can help make up for dumped Charisma on the rare occasions that you feel the need to make Charisma checks. Giving up damage resistance hurts, but it may be worth the trade.
Ravenite^EGtW: +2 Str, +1 Con, Darkvision. Vengeful Assault is guaranteed to get used. Barbarians tend to get hit a lot, and more attacks means more damage output early in a fight.

Default Rules:

Draconblood^EGtW: Bad ability spread.
Ravenite^EGtW: Better ability scores for the Barbarian than the standard Dragonborn, and you can survive without the Dragonborn's damage resistance. Ravenite adds Darkvision, a Constitution increase, and Vengeful Assault which offers an occasional boost to your damage output.

Elf

Wildemount elves share the core traits of PHB elves, but Wildemount adds two new subraces. See above for more information on other elf subraces.

Customized Origin:

Pallid Elf^EGtW: Advantage on Wisdom (Insight) can helpful in social situations where the Barbarian frequently struggles, but beyond that Invisibility as an innate spell is the only benefit. That's simply not enough, and there are a number of other racial options with similar benefits.
Sea Elf^{EGtW / MToF}: See above under the general Races section.

Default Rules:

Pallid Elf^EGtW: Nothing useful for the Barbarian.
Sea Elf^{EGtW / MToF}: See above under the general Races section.

Firbolgs^EGtW: See above under the general Races section.

Genasi^EGtW: See above under the general Races section.

Goblin^EGtW: See above under the general Races section.

Halfling^PHB

Wildemount halflings share the core traits of PHB halflings, but Wildemount adds a new subrace. See above for information on other halfling subraces.

Customized Origin:

Lotusden^EGtW: The innate spellcasting will be very unreliable, and you can't use it while raging.

Default Rules:

Lotusden^EGtW: Nothing useful for the Barbarian.

Hobgoblin^EGtW: See above under the general Races section.

Goliath^EGtW: See above under the general Races section.

Kenku^EGtW: See above under the general Races section.

Orc^EGtW: See above, under "Races of Eberron". Wildemount uses the updated Orc racial traits rather than the original traits published in Volo's Guide to Monsters.

Tabaxi^EGtW: See above under the general Races section.

Tortle^EGtW: See above under the general Races section.

Skills

Animal Handling (Wis): Not really helpful for the function of the Barbarian, but the flavor makes sense.
Athletics (Str): The only Strength-based skill, Athletics is more than climbing and swimming. You use Athletics for grappling and for pushing enemies, both of which can be excellent options for Barbarians.
Intimidation (Cha): If you're built with a bit of Charisma for the Berserker's Intimidating Presence, you can be good at Intimidate. Otherwise, skip it.
Nature (Int): Intelligence is a dump stat for Barbarians, but if no one in the party has access to Nature it's not an awful choice.
Perception (Wis): One of the most important skills in the game. At least two people in the party should have it, but more is always better.
Survival (Wis): Adventuring tends to involve a lot of wandering around in untamed wilderness, so Survival can be very helpful to your party.

Background

This section does not address every published background, as doing so would result in an ever-growing list of options which don't cater to the class. Instead, this section will cover the options which I think work especially well for the class, or which might be tempting but poor choices. Racial feats are discussed in the Races section, above.

Barbarians don't do a lot with skills, and the skills you generally want are on the Barbarian's class skill list. When looking for a Background, try to pick up skills which complement your existing skill proficiencies and which capitalize on your ability scores.

If you're having trouble deciding, here are some suggestions:

City Watch^SCAG: Athletics is great, Insight may be a hard choice and you won't get much from the ability to speak two languages with your garbage Charisma.
Criminal^PHB: This might work for a Wolf Totem Barbarian, especially if you have a Rogue in the party who can be stealthy with you.
Folk Hero^PHB: Two skills from the Barbarian skill list, and a couple of tool proficiencies. Artisan's Tools are probably a waste, but proficiency with land vehicles covers things like wagons which adventurers frequently travel in until long-distance magical travel becomes available. The theme works really well for a Barbarian who made a name for themself among their tribe, then set out to do some more heroics.
Hermit^PHB: Medicine and herbalism can be useful for a Barbarian, especially if you don't have a healer in the party, but they're still not fantastic options.
Outlander^PHB: The go-to option for Barbarians, you get two skills from the Barbarian list, but the other proficiencies are largely wasted.
Sailor^PHB: Great for aquatic campaigns. Two good skills from the Barbarian list, and boats!
Soldier^PHB: Somewhere between the Folk Hero and the Outlander. Two good skills from the Barbarian skill list, and some fun tool proficiencies which likely won't be very impactful but you still have a decent chance of actually using them successfully.
Uthgardt Tribe Member^SCAG: Two important Barbarian skills, but instruments, artisan's tools, and languages are generally wasted on the Barbarian.

Feats

This section does not address every published feat, as doing so would result in an ever-growing list of options which don't cater to the class. Instead, this section will cover feats which I think work especially well for the class or which might be tempting but poor choices.

Alert^PHB: Feral Instinct does plenty on its own, so you shouldn't need this.
Charger^PHB: Great for closing to melee, but situational. If you can't get into melee range with your movement it may be better to use your action to throw some javelins.
Crusher^TCoE: At a glance this looks like it's a great fit for the Barbarian, but it's not as useful as it looks. The ability increases are great, but knocking enemies away you is usually a bad choice for the Barbarian, and since you have Reckless Attack it's unlikely that you'll benefit from granting Advantage after a critical hit. Your allies will benefit from the Advantage effect, but if that's something you want you should consider Path of the Totem Warrior's Totem Spirit (Wolf) feature.
Chef^TCoE: Potentially more impactful than Tough or a +2 Constitution increase (unless you're using Unarmored Defense), Chef provides a lot that the Barbarian can benefit from. The Constitution increase is obviously great, and the bonus healing on a Short Rest is helpful since the Barbarian tends to take a lot of damage and relies heavily on natural healing. The snacks, despite being small in number, provide an easy way to quickly acquire temporary hit points which can further stretch your party's limited healing resources. The snacks are eaten as a Bonus Action, so if your subclass does't lean heavily on your Bonus Action you can shovel snacks into your mouth while raging to mitigate whatever damage you're taking. The damage resistance provided by Rage will make the temporary hit points more impactful, too.
Dual Wielder^PHB: Two-Weapon Fighting can be a good way to bring your bonus Rage damage into play more frequently, but since Two-Weapon Fighting uses your bonus action, this is a bad option for barbarians subclasses which use their Bonus Action heavily. If your Bonus Action isn't doing much, combining Dual Weilder with Brutal Critical could be effective, though the smaller damage die between a d8 weapon and a d12 weapon makes the math complicated because you need to weigh the improve likelihood of scoring a critical hit against rolling bigger dice on a critical hit.
If you're considering two-weapon fighting, be sure to consider taking Fighting Initiate for Fighting Style (Two-Weapon Fighting). The numeric bonus to damage is more effective offensively than upgrading from d6 to d8 damage dice. However, Dual Wielder provides an AC bonus and the larger damage dice synergize nicely with Brutal Critical.
Durable^PHB: Rage gives you resistance to weapon damage types, but you'll still face problems from spells, and with only medium armor the Barbarian's hit points typically rise and fall very far very quickly. Magical healing goes a long way, but much of your healing will come from your Hit Dice. Ideally your Constitution will be high enough to give you a big pool of hit points, so the Durable feat can go a really long way to keep your hit points high throughout the day.
Fighting Initiate^TCoE: Very few options will be more consistently effective than increasing one of your ability scores. High-level barbarians who are fishing for critical hits might enjoy Fighting Style (Great Weapon Fighting), but the math still isn't great. Blind Fighting is tempting since barbarians don't have a way to handle invisibility, and Interception/Protection are tempting for barbarians without a feature that uses their Reaction consistently.
Grappler^PHB: Just a terrible feat in general. You don't need it to grapple successfully.
Great Weapon Master^PHB: Barbarians are all about two-handed weapons, and Great Weapon Master offers some great options. Berserker Barbarians will find the extra attack benefit useful in fights with numerous weak enemies, allowing them to reserve their Frenzy for fights with large single enemies.
Heavily Armored^PHB: Rage doesn't function while you're wearing heavy armor.
Heavy Armor Master^PHB: Rage doesn't function while you're wearing heavy armor.
Inspiring Leader^PHB: This is generally better for more charismatic characters like Bards or Paladins, but temporary hit points are great for Barbarians. If you're building to utilize Frightful Presence, this might be worthy of consideration.
Mage Slayer^PHB: Only useful in games which feature an abnormally large number of spellcasters.
Martial Adept^PHB: One superiority die means that you might get to use your maneuvers two or three times a day at most. Feats should be more consistently useful.
Medium Armor Master^PHB: You won't be doing much stealth unless you went for Wolf Totem and have other stealthy people in your party, and the potential bonus to AC isn't enough to justify this feat on its own.
Mobile^PHB: You already get a speed boost, and Eagle totem will provide similar benefits.
Mounted Combat^PHB: Fighting while mounted can be a great option for Barbarians, and you have plenty of hit points to absorb any attacks which might target your mount.
Piercer^TCoE: The only weapon which you're likely to use this with is the Pike. I wouldn't consider this a go-to combination, but if you're building around critical hits the additional damage die stacks with Brutal Critical and also provides the reroll benefit of Savage Attacker. It might work if you can spare a feat for it, which is slightly easier since you also get a +1 Strength increase.
Polearm Master^PHB: The Barbarian has very few options which require you to be within 5 ft. of a target. The base class offers Retaliation, and the Totem Warrior has a couple options (Totem Spirit (Wolf) and Totemic Attunement (Bear)), but if you're fine not relying on those options most of the time a reach weapon and Polearm Master can be tempting. The bonus attack provided by the feat is especially interesting since you can get the damage of a two-handed weapon while still getting as many attacks as though you were using two-weapon fighting. However, there are some Barbarian features which allow you to make extra attacks as a Bonus Action, and Rage is activated as a Bonus Action so you may find that the bonus polearm attack frequently goes unused. The ability to make an attack when something enters your reach is nice, but considering barbarians usually handle threats by charging them first you'll likely find that this benefit also rarely applies.
Resilient^PHB: I probably would not take this before you have hit your maximum in Strength and possibly Constitution, but Resilient (Wisdom) can protect you from magic which is frequently used to incapacitate characters like barbarians who typically have poor mental stats.
Savage Attacker^PHB: This is a bad feat. The largest damage die (d12), yields an average of 2 extra damage per turn. The absolute best case scenario is a half-orc berserker with Brutal Critical critting with a greataxe, but even then it's still only around 4.45 extra damage at the absolute most, and it's still limited to once per turn.
Sentinel^PHB: This is fantastic for Defender builds, and solves the "Tank Falacy" issues faced by many barbarian subclasses, including the the Totem Warrior (bear totem) and the Path of the Zealot. Forcing enemies to remain in melee with you prevents them from running away from you in order to attack your allies.
Shield Master^PHB: The best part of this is probably the ability to shove enemies (possibly shoving them prone) as a bonus action. Wolf totem provides a similar benefit.
Skill Expert^TCoE: Barbarians have frustratingly few options outside of combat, and adding an extra skill can diversify your capabilities. Expertise in Athletics can make you nearly unstoppable at Grappling and Shoving, especially once you add the Advantage on Strength checks from Rage.
Skilled^PHB: Helpful if your party has large skill gaps, but Barbarians aren't very good at skills, so your utility is severely limited.
Skulker^PHB: Even if you are in a sneaky party, you should be leaping from hiding to murder things.
Slasher^TCoE: The speed reduction is a great way to keep enemies from escaping you. Most creatures have a speed around 30 feet, and between Fast Movement and the speed penalty on your target, you're very hard to escape even if the target Dashes. The critical hit benefit is great, too, but you can't count on critical hits so you need to consider the ability increase and the speed reduction as the core of the feat. Like Sentinel, this is a great way to address the "Tank Falacy" because it makes it so much more difficult for enemies to simply ignore you and walk past you to attack your allies.
Tavern Brawler^PHB: If you want to go for Grappler, this feat complements it nicely.
Tough^PHB: You need too many ability increases to make room for this feat unless you're playing a Variant Human. Instead, boost your Constitution. If you're playing a Variant Human and this is the feat you plan to take, consider a Hill Dwarf instead.

Weapons

Handaxe: Your go-to option for two-weapon fighting.
Javelin: A great disposable ranged option when you're too far away to move into melee in one turn.
Greataxe: Brutal Critical means that a bigger damage die is better for you.
Greatsword: More reliable damage than the Greataxe, but not as useful with Brutal Critical.
Maul: Basically a blunt greatsword.

Armor

Multiclassing

This section briefly details so obvious and enticing multiclass options, but doesn't fully explore the broad range of multiclassing combinations. For more on multiclassing, see my Practical Guide to Multiclassing.

Fighter: The Fighter's Fighting Style ability is decent if you go for two-weapon fighting, but Two-Weapon Fighting is hard since Barbarians already have several options which allow them to attack as a bonus action, allowing them to match TWF number of attacks while using a two-handed weapon. 2nd level brings Action Surge, which is fantastic on any character. At 3rd level consider the Champion archetype to pick up Improved Critical, which will double how often you get to use Brutal Critical.
Monk: Unarmored Defense abilities don't stack. You use whichever you got first, according to the official FAQ.
Rogue: A dip into Rogue for Expertise in Athletics will go a long way if you plan to use Shove or Grapple, but without the Fighter's big number of attacks Shove isn't always a great option. Cunning Action isn't always helpful for a Barbarian and conflicts with the numerous class features which use a bonus action (Rage, etc.), so most builds shouldn't go past level 1.
Wizard: Barbarians have almost exactly opposite abilities to Wizards, so there isn't a lot of room for compatibility.

Magic Items

Common Magic Items

Moon-Touched Sword^XGtE: This solves two problems for the martial characters. First, the sword glows almost as brightly as a torch, allowing you to see in dark places without devoting a hand to a torch and without asking your allies to cast light or something. Second, and more important, it allows you to overcome damage resistance to non-magic attacks. Resistances like this are common as you gain levels, and the Moon-Touched Sword is an inexpensive way to overcome them until a better weapon comes along.

Uncommon Magic Items

Adamantine Armor^DMG: The protection against critical hits is nice since Reckless Attack grants enemies Advantage against you, doubling the likelihood that you'll suffer a critical hit.
Boomerang, +1^DMG: Helpful for thrown weapon for Strength-based builds that need an occasional ranged option, but javelins are cheaper and you won't feel the need to rush to recover them.
Cloak of Protection^DMG: Good on any character, but it requires Attunement and it's not very interesting.
Eyes of the Eagle^DMG: Perception is the most frequently rolled skill in the game, and while the Barbarian isn't fantastic with skills Perception is still one of your better skill options. Pass this off to someone with a better bonus if you can, but you may still find this helpful if that's not an option.
Gloves of Missile Snaring^DMG: Similar to the Monk's Deflect Missiles feature, this is an interesting defensive option for melee characters. However, ranged missile attacks are relatively rare since so many monsters can't fight at range and many ranged enemies will be spellcasters, so this is situational by nature.
Lantern of Revealing^DMG: An excellent counter to invisibile enemies for a class without a built-in way to handle them.
Mithral Armor^DMG: Negate the Disadvantage on stealth checks imposed by half plate. Just as effective as +1 Breastplate, and it's one rarity lower.
Periapt of Wound Closure^DMG: Barbarians have poor AC and huge hit dice, so spending hit dice is a crucial part of how you stay alive. Doubling the efficiency of those hit dice will keep you from becoming a constant tax on your party's healing resources.
Stone of Good Luck^DMG: Excellent on literally any character, but if you just want better defense a Cloak of Protection may be more effective. Stone of Good Luck shines if you're heavily reliant on skills and ability checks.
Weapon, +1^DMG: Barbarians are all about weapon attacks, so a numeric bonus to attack and damage is hard to beat. As you gain levels weapons more interesting than a +X bonus to attack/damage may be more interesting and more effective, but at the Uncommon rarity nothing can compete with a +1 Weapon for your offensive needs.
Winged Boots^DMG: Excellent on its own, but Winged Boots are more limited in use than a broom of flying, and they require Attunement.

Rare Magic Items

Amulet of Health^DMG: Setting your Constitution to 19 means that you don't need to put Ability Score Increases into it unless you're really certain that you want 20 Constitution. Less ASI's into Constitution means more room for feats, but if you want to use Unarmored Defense or if you ever reach level 20 you'll probably want your Constitution at 20.
Armor of Resistance^DMG: Excellent, but unpredictable in most games since you can't perfectly predict what sort of damage you'll face. Fire and poison are safe choices.
Armor, +1^DMG: +1 AC, no attunement. Nothing fancy, but very effective.
Belt of Dwarvenkind^DMG: For non-dwarves, Darkvision and resistance to poison is extremely useful since most barbarians don't get a way to provide them on your own. The increased Constitution is nice, too, especially if you're planning to sit at 18 Constitution for a long time. Barbarians approach level 20 may consider raising their un-improved Constitution to 20 to enjoy their new 24 Constitution, but until level 20 that +2 bonus is really nice.
Belt of Giant Strength (Hill)^DMG: The fact that this item exists makes putting ability score increases into Strength feel a bit silly. Imagine rushing to get to 20 Strength then finding an item that raises your Strength to 21 (more with higher rarities). Still, if you can get one you absolutely should.
Bracers of Defense^DMG: As much AC as a shield. If you're relying on Unarmored Defense, these are fantastic and can easily make up the difference between +X armor and Unarmored Defence's AC bonus. Given the choice, you might prefer a Cloak or Ring of Protection.
Cloak of Displacement^DMG: Among the best defensive items in the game. Taking damage from any source (spells, etc.) suppresses the effect temporarily, so make a point to kill anything that can damage you without an attack roll.
Flametongue^DMG: Mathematically the +2 bonus to attack rolls from a +2 weapon will be a more consistent improvement to your damage output (especially with the growing damage bonus from Rage), but the Flametongue is way more fun. The 2d6 damage is multiplied on critical hits, too, and since barbarians score critical hits frequently thanks to Reckless Attack, multiplying the damage from Flametongue can provide a significant source of damage output.
Periapt of Proof Against Poison^DMG: Poison damage is very common across the full level range, so immunity to it is a significant improvement in your durability.
Ring of Evasion^DMG: A great way to mitigate damage from AOE spells and things like breath weapons which can often be problems from front-line martial characters.
Ring of Protection^DMG: Cloak of Protection is lower rarity and has the same effect.
Ring of Resistance^DMG: Most of the time you'll want something common like fire, but get resistance to psychic damage if you can, and a bear totem barbarian has resistance to all damage.
Ring of Spell Storing^DMG: You can't cast spells while raging, so my usual Absorb Elements+Shield recommendation doesn't work.
Sword of Life Stealing^DMG: Between Extra Attack and Reckless Attack, you're unusually likely to roll natural 20's on your attacks, making the Sword of Life Stealing very appealing. The extra damage is great, and the temporary hit points will mitigate Reckless Attack's drawback.
Sword of Wounding^DMG: Persistent damage that stacks with itself. It's only 1d4 and only once per turn, but it stacks with itself and "once per turn" means that if you can attack again outside of your own turn (Opportunity Attacks, etc.) you can get additional dice very quickly.
Vicious Weapon^DMG: Mathematically this is worse than a +2 weapon in every way. If you really like the natural 20 effect for some reason, go for a Sword of Life Stealing.
Weapon, +2^DMG: Mathematically spectacular. It's difficult to beat the math here.

Very Rare Magic Items

Animated Shield^DMG: Tempting for anyone not fighting with a one-handed weapon, but a Cloak of Protection is two rarities lower, works persistently, and arguably provides a better numeric bonus.
Armor, +2^DMG: +1 AC, no attunement. Nothing fancy, but very effective.
Belt of Giant Strength (Frost, Stone, Fire)^DMG: Much like a +X weapon, it's hard to beat the math here. Raising your Strength above 20 is a massive benefit, and going up as high as 25 is spectacular. Between that and Reckless Attack you hit so reliably that you almost can't miss.
Dancing Sword^DMG: A great way to spend you Bonus Action if you don't have many uses for it, but the sword only uses your attack and damage modifiers, so it can't benefit from feats, class features, etc.
Frost Brand^DMG: Less damage than the Flame Tongue, but higher rarity and it requires attunement. Yes, you get resistance to fore damage, but you can get that from dozens of other sources by this level.
Manual of Bodily Health^DMG: Permanent Constitution bonus and raises your cap by 2. Unless you're using a magic item that fixes your Constitution as a specific score, this is excellent.
Manual of Gainful Exercise^DMG: If you reach level 20 and get the +4 Strength increase, you can hit 26 Strength and exceed the Strength provided by a Belt of Giant's Strength of the same rarity.
Manual of Quickness of Action^DMG: Unless you're worried about the cap on attuned items, a Cloak or Ring of Protection will be more effective.
Ring of Regeneration^DMG: Short Rests exist for a reason. If you want this, consider a Periapt of Wound Closure instead.
Sword of Sharpness^DMG: Basically a Vicious Weapon with a damage boost. The limb removal is neat, but only occurs on average once every 400 attacks (more often with Reckless Attack, but still not enough to make this good). A +3 weapon is massively more reliable and effective.
Weapon, +3^DMG: Mathematically spectacular. It's difficult to beat the math here.

Legendary Magic Items

Belt of Giant Strength (Cloud, Storm)^DMG: As good as a +4 weapon for Strength-based character, and that doesn't even consider Athletics checks or saves.
Blood Fury Tattoo^TCoE: The first ability provides a great damage boost which also heals you, and since it's "extra damage" the damage is multiplied on a critical hit. The second ability provides a way to counterattack using your Reaction, and with Advantage on that attack it's an easy and reliable boost to your damage output.
Ioun Stone (Mastery)^DMG: Proficiency Bonuses apply to a lot of things and a +1 bonus goes a long way. Attacks, saves, skills, etc. all benefit.
Luck Blade^DMG: Bonuses to attacks and saves, a once per day reroll, and it can cast Wish a few times (maybe. 1d4-1 could be zero). Green if it can't cast Wish.
Ring of Spell Turning^DMG: Given the choice, I would much rather haqve a Mantle of Spell Resistance simply because the Ring of Spell Turning doesn't provide any protection against area effect spells. Otherwise, this is a really fun item, and if it provided Advantage on saves against area of effect spells it would shoot straight up to blue.
Ring of Three Wishes^DMG: Use this to do one of the things that risks permanently removing the ability to cast Wish, such as granting 10 creatures permanent resistance to once damage type. If you lose the ability to cast Wish, pass this off to another ally who will never be able to cast Wish by any other means. Repeat until the last charge is used.
For more help with Wish, see my Practical Guide to Wish.
Rod of Lordly Might^DMG: Allows you to easily change your weapon damage type, and provides three powerful offensive abilities which work in a variety of situations. Unfortunately all of the weapon types (with the exception of the Flametongue) are one-handed, which is hard for many barbarians.
Scarab of Protection^DMG: An upgrade from the Mantle of Spell Resistance, the Scarab of Protection adds a limited benefit against necromancy and undead creatures, and doesn't take up your cloak slot, leaving you free to take items like a Cloak of Protection or Cloak of Invisibility instead.
Vorpal Sword^DMG: Mostly useful as a +3 weapon, but thanks to Reckless Attack you'll roll natural 20's fairly often.

Example Build - Half-Orc Barbarian (Berserker)

Gnarg the Half-Orc Berserker

The pronounced muscles of his broad shoulders and back ripple with the simple action of brushing a whetstone along the blade of his greataxe. He wears no armor, a practice that has resulted in many scars from what must have been dozens of battles. He lifts his head from his task, turning it slightly to reveal a tusked mouth and heavy brow. The half-orc knows you’re looking.

-- Boxed text provided by dScryb ^{(affiliate link)}

This is a "Staple Build". This build is simple, and relies on options from the SRD and the Basic Rules wherever possible. If you need a functional build with nothing fancy or complicated, this is a great place to start.

This is a very simple build. Barbarians have very few decision points, and the biggest tactical decision they require in an encounter is whether or not to rage. Berserker adds the additional choice of potentially entering a Frenzy, but even that shouldn't be especially stressful.

Abilities

We'll mostly use the example ability scores described above, but we'll switch the Strength and Constitution so that we can get 16 in both after the Half-orc's racial ability score increases.

	Base	Increased
Str	14	16
Dex	14	14
Con	15	16
Int	8	8
Wis	10	10
Cha	10	10

Race

Half-Orc. Savage Attacks works great with greataxes, and I can't think of a weapon that says "barbarian" more than a greataxe. It also stacks with Brutal Critical, so you get to roll big piles of d12's at high levels.

Skills and Tools

Half-orcs get Intimidation for free, so we'll pick up Nature and Perception.

Background

Soldier. Of the limited number of options in the basic rules, Soldier is one of the best options for us. Since we already get Intimidation proficiency, we can replace the redundant proficiency with something else. We'll keep Athletics, and you can use the replacement proficiency to get Survival.

Folk Hero works equally well in terms of skills, and you can use your class skill proficiencies to get Animal Handling and Survival to turn both into open skill proficiency slots if you want something not on the Barbarian skill list.

Levels

Level	Feat(s) and Features	Notes and Tactics
1	Rage Unarmored Defense	For your starting gear, take a greataxe, two handaxes, and the explorer's pack and javelins. You don't start with armor, but with 14 Dex and 16 Con Unarmored Defense gives you 15 AC. You might buy yourself a shield, but that will mean putting down your greataxe, and you've got 15 hit points for a reason, and Rage will give you damage resistance. At this level you can only rage twice per day, but at first level adventuring days tend to be short because characters are so fragile, so you should be able to rage in most encounters.
2	Reckless Attack Danger Sense	Reckless Attack is a great ability, but obviously it comes with risks. At this level I recommend only using it in fights against powerful single foes so you're not taking repeated hits from groups of weak enemies, and even then consider raging at the same time to offset the additional damage you will inevitably take. Danger Sense is helpful for mitigating damage from AOE effects which will typically deal damage types not resisted by Rage. At this point you may have enough gold for a suit of Scale Mail, which will net you +1 AC, but after that start saving gold until you can get Half Plate.
3	Primal Path: Path of the Berserker Frenzy	Our first subclass ability is Frenzy. It's basically just better Rage, but you suffer a level of exhaustion when your rage ends. You don't want to go past two levels of exhaustion, and now that you have three rages per day that's a possibility. The combination of Frenzy and Reckless Attack is the reason greataxes are appealing for the Barbarian, so when you need to deal a bunch of damage in a hurry you can Rage, Frenzy, and use Reckless Attack to deal a whole bunch of damage in a hurry.
4	Ability Score Improvement (Strength 16 -> 18)	More Strength means more attack and more damage.
5	Extra Attack Fast Movement	5th level is an important milestone in 5e. Martial classes get Extra Attack, which roughly doubles your damage output. 5th level also requires proportionately more encounters worth of experience before you gain another level than any other level, so you're going to spend a lot of time at 5th level. Between Frenzy's Bonus Action attack and Extra Attack, you get three attacks with Advantage (Reckless Attack) for a total of 6 d20 rolls, giving your probability of more than 26% to roll at least one natural 20, and every time you crit you're dealing 3d12+Str damage, which feels really satisfying.
6	Mindless Rage	Attacking a barbarian mentally is the easiest way to shut them down, so Mindless Rage is a significant defensive buff.
7	Feral Instinct	Going first feels great. It's usually not very important for barbarians because you don't need to cast a spell to alter the layout of an encounter or something, but it's still really nice.
8	Ability Score Improvement (Strength 18 -> 20)	20 Strength means that you're as strong as you'll be until you reach 20th level or find a really nice magic item.
9	Brutal Critical (1 die) Rage Damage +3	Adding another d12 roughly 25% of the time means that you're dealing something like 1.5 extra damage per turn. On average that's not much, but it feels very satisfying to roll 4d12 on a critical hit.
10	Intimidating Presence	Intimidating Presence is rarely useful because it eats your entire action. You could still Frenzy and attack as a bonus action, but I think the most likely use case for this is to begin a Rage solely for the purpose of chasing someone around and screaming at them.
11	Relentless Rage
12	Ability Score Improvement (Constitution 16 -> 18)	A Constitution increase means that your Unarmored Defense AC rises to 16, so Half Plate is still better. But you get a bunch of extra hit points, which is great.
13	Brutal Critical (2 dice)	Each greataxe hit die added by Brutal Critical adds roughly 1.5 extra damage per round on average. Between Savage Attacks and Brutal Critical, you're now rolling 4d12+Str on a critical, which feals really awesome.
14	Retaliation	Finally a good reason not to get as much AC as possible, Retaliation means that taking damage increases your damage output. Of course, but this level an AC of 17 is not safe by any stretch of the imagination, so don't go dumping your armor to try to trigger this. You won't need to.
15	Persistent Rage Rage Damage +4	Since you're a Berserker, ending a rage can carry a bigger consequence than it does for other barbarians, and effects that prevent you from acting like paralysis can force your race to end early.
16	Ability Score Improvement (Constitution 18 -> 20)	Your Unarmored Defense now matches the AC provided by half plate. Drop the armor so you're no longer suffering Disadvantage on Dexterity (Stealth) checks and wearing 40 lbs. of clothing. Of course, if you have magic armor that changes the math.
17	Brutal Critical (3 dice)	Another critical hit die, another 1.5 average damage per round. You're up to 5d12 on a critical hit now, which is pretty great,.
18	Indomitable Might	Once in a while you need to grapple, lift something, break something, etc. and by this level you already have 20 Strength, so your minimum result is 20. That's easily enough to pass normal ability check DCs, but you may lose grapple checks on very rare occasion,
19	Ability Score Improvement (Dexterity 14 -> 16)	A bump in Dexterity doesn't do much for you, but at the very least you get better initiative and +1 AC. If you don't want to increase Dexterity, this extra ability score improvement is clear indication that you have room to consider a feat.
20	Primal Champion	+2 to hit, +2 damage, minimum of 24 on all Strength checks, and +40 hit points on top of what you got just for gaining a level.

DnD 5e - The Barbarian Handbook

Disclaimer

Introduction

Barbarian Class Features

Optional Class Features

Ability Scores

Races

AarakocraEEPC

AasimarVGtM

Aasimar (DMG Variant)DMG

BugbearVGtM

Custom LineageTCoE

DragonbornPHB

DwarfPHB

ElfPHB

FirbolgVGtM

GenasiEEPC

GithMToF

GnomePHB

GoblinVGtM

GoliathEEPC

Half-ElfPHB

Half-OrcPHB

HalflingPHB

HobgoblinVGtM

Human

KenkuVGtM

KoboldVGtM

LizardfolkVGtM

LocathahLR

OrcVGtM

TabaxiVGtM

TieflingPHB

TortleTP

TritonVGtM

VerdanAcInc

Yuan-Ti PurebloodVGtM

Races of Eberron

ChangelingERLW

KalashtarERLW

ShifterERLW

WarforgedERLW

Dragonmarks

Dragonmarked DwarfERLW

Dragonmarked ElfERLW

Dragonmarked GnomeERLW

Dragonmarked Half-ElfERLW

Dragonmarked Half-OrcERLW

Dragonmarked HalflingERLW

Dragonmarked HumanERLW

Races of Ravnica

CentaurGGTR

LoxodonGGTR

MinotaurGGTR

Simic HybridGGTR

VedalkenGGTR

Races of Theros

LeoninMOoT

SatyrMOoT

Races of Wildemount

DragonbornPHB

Elf

HalflingPHB

Skills

Background

Feats

Weapons

Armor

Multiclassing

Magic Items

Common Magic Items

Uncommon Magic Items

Rare Magic Items

Very Rare Magic Items

Legendary Magic Items

Example Build - Half-Orc Barbarian (Berserker)

Abilities

Race

Skills and Tools

Background

Aarakocra^EEPC

Aasimar^VGtM

Aasimar (DMG Variant)^DMG

Bugbear^VGtM

Custom Lineage^TCoE

Dragonborn^PHB

Dwarf^PHB

Elf^PHB

Firbolg^VGtM

Genasi^EEPC

Gith^MToF

Gnome^PHB

Goblin^VGtM

Goliath^EEPC

Half-Elf^PHB

Half-Orc^PHB

Halfling^PHB

Hobgoblin^VGtM

Kenku^VGtM

Kobold^VGtM

Lizardfolk^VGtM

Locathah^LR

Orc^VGtM

Tabaxi^VGtM

Tiefling^PHB

Tortle^TP

Triton^VGtM

Verdan^AcInc

Yuan-Ti Pureblood^VGtM

Changeling^ERLW

Kalashtar^ERLW

Shifter^ERLW

Warforged^ERLW

Dragonmarked Dwarf^ERLW

Dragonmarked Elf^ERLW

Dragonmarked Gnome^ERLW

Dragonmarked Half-Elf^ERLW

Dragonmarked Half-Orc^ERLW

Dragonmarked Halfling^ERLW

Dragonmarked Human^ERLW

Centaur^GGTR

Loxodon^GGTR

Minotaur^GGTR

Simic Hybrid^GGTR

Vedalken^GGTR

Leonin^MOoT

Satyr^MOoT

Dragonborn^PHB

Halfling^PHB