Updated:

Helmet by version

VersionCommand
Java 1.21.5 and later/give @p minecraft:netherite_helmet[enchantments={protection:4,unbreaking:3,mending:1,respiration:3,aqua_affinity:1}]
Java 1.20.5–1.21.4/give @p minecraft:netherite_helmet[enchantments={levels:{protection:4,unbreaking:3,mending:1,respiration:3,aqua_affinity:1}}]
Java 1.16–1.20.4/give @p minecraft:netherite_helmet{Enchantments:[{id:"minecraft:protection",lvl:4s},{id:"minecraft:unbreaking",lvl:3s},{id:"minecraft:mending",lvl:1s}]}

Item data moved from NBT { } to components [ ] in 1.20.5, and the levels wrapper was removed in 1.21.5. Netherite was added in 1.16; use diamond on older versions.

Full set (1.21.5 and later)

/give @p minecraft:netherite_helmet[enchantments={protection:4,unbreaking:3,mending:1,respiration:3,aqua_affinity:1}]
/give @p minecraft:netherite_chestplate[enchantments={protection:4,unbreaking:3,mending:1}]
/give @p minecraft:netherite_leggings[enchantments={protection:4,unbreaking:3,mending:1,swift_sneak:3}]
/give @p minecraft:netherite_boots[enchantments={protection:4,unbreaking:3,mending:1,feather_falling:4,depth_strider:3,soul_speed:3}]

On 1.20.5–1.21.4, wrap each list in enchantments={levels:{…}}.

Best enchantments per piece

PieceEnchantments
AllProtection IV, Unbreaking III, Mending
HelmetRespiration III, Aqua Affinity
LeggingsSwift Sneak III (1.19+)
BootsFeather Falling IV, Depth Strider III, Soul Speed III

Depth Strider and Frost Walker normally cannot be combined; /give allows it, but pick one. Thorns returns damage to attackers but wears your armor faster.

Higher levels do not keep helping

/give accepts levels above IV, but protection enchantments stop at an 80% total damage reduction across all pieces. Protection IV on four pieces already gives about 64%, so around level V is enough. For more toughness, add the Resistance effect.

Equip it directly and make it unbreakable

/item replace entity @p armor.head with minecraft:netherite_helmet[unbreakable={}]

/item replace (Java 1.17+) puts the piece straight into the armor slot. Slots are armor.head, armor.chest, armor.legs and armor.feet. On 1.20.4 and earlier, unbreakable is written {Unbreakable:1b}.

Common problems

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