Dictionary
Touch target
The tappable area of an interactive element on a touchscreen. Should be at least 44×44px so it's easy to hit accurately.
In more detail
What It Means
A touch target is the tappable area of a button, link, or form control on a touchscreen, and it needs to be at least 44 by 44 pixels to be reliably hit with a finger. Anything smaller becomes hard to tap accurately, especially for anyone with limited dexterity.
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