Fitts’s Law
A model predicting that the time to reach a target depends on its size and distance — bigger, closer targets are faster and easier to hit.
Why it matters
It is the physics behind half of interface layout: why primary buttons are big, why context menus open at the cursor, and why anything important should not be a 12px icon in a far corner. Break it and every interaction gets a little slower — thousands of times a day.
Feel it
Your own milliseconds, measured live — time grows with distance and shrinks with size.
The numbers
- Bigger and closer = faster — time grows with distance, shrinks with size
- Edges and corners — the cursor cannot overshoot them, making them effectively infinite targets
Related terms
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