"You got a Small Key! Use it to open a locked door. You can use the key only in this dungeon."
— In-game description
A Small Key from Twilight Princess

Small Keys ( Kagi?, Key) are recurring items in the Legend of Zelda series. As suggested by their name, they are small keys that are found throughout dungeons. They allow Link to open locked doors or Key Blocks; however, they cannot be used or taken outside of the dungeon in which they are found in most games. In most cases, Link must complete a task or puzzle in order to acquire a necessary key. The only locked doors that a Small Key will not open is the door to the Boss's lair, as those doors require a Boss Key, and a few other doors in A Link to the Past, which require a Big Key. As certain dungeons have locked rooms that are not mandatory to access, it is possible to have more Small Keys than needed.

Small Keys in The Legend of Zelda and The Adventure of Link can be taken outside the dungeons in which they are found and can be used in any dungeon throughout Hyrule. Certain Merchants in The Legend of Zelda's Overworld offer Small Keys for sale, but because each dungeon always generates the required amount of keys, buying one is considered to be a waste of Rupees. This can, however, be helpful if the player has become frustrated with searching. Additionally, no special key exists for the door to the Boss room. There also exists a Magical Key that can unlock doors like a Small Key, but be used unlimited number of times.

In both game counterparts Ocarina of Time and Majora's Mask, they are found in small treasure chests.

"A key that can unlock doors inside shrines."
Breath of the Wild description
A Small Key from Breath of the Wild

In The Legend of Zelda: Breath of the Wild, Small Keys appear in Shrines and appear as part of certain trials. They appear to be constructed with ancient Sheikah Technology indicating they are Sheikah made.

See also