Unbreaking

Unbreaking is an enchantment that gives a chance for an item's durability not to be reduced when it is used, effectively increasing the item's durability.

Usage
For most items, there is a $$\frac{100}{level+1} %$$ chance that using the item reduces 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 ~25%/36%/43% longer.

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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