Show Durability is a Fabric mod that displays the durability of items in inventories and in the hotbar directly on the item with a number. The durability display can be toggled with a keybind (B by default). The mod requires Fabric API to be installed (since version 1.1.0), and should only be installed on the client. It works in singleplayer and multiplayer.
Thomilist/show-durability
A Minecraft mod for Fabric which shows the durability of items in inventories and in the hotbar directly on the items with a number.
JavaMIT