Unbreaking

Unbreaking is an enchantment that gives a chance for an item to avoid durability reduction when it is used, effectively increasing the item's durability.



Obtaining
Unbreaking I, Unbreaking II, and Unbreaking III can be acquired using an enchanting table, by fishing, finding an enchanted book in dungeon chests, and by trading with a librarian villager.

Usage
For most items, there is a $$\frac{100}{level+1} \%$$ chance that using the item reduces durability. Meaning the item has a 50%/~66%/75% chance of not using any durability. On average, tools last $$level+1$$ times as long. For armor, there is a $$\left( 60 + \frac{40}{level + 1} \right) \%$$ chance a use reduces durability, meaning each durability hit against Unbreaking armor has a ~20%/27%/30% chance of being ignored. On average, armor lasts $$\frac{1}{0.6+\frac{0.4}{level+1}}$$ times as long.

When durability is reduced by multiple points, as when hooking a mob with fishing rods or getting blown up with TNT, Unbreaking is applied for each point of reduction.

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