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Click targets as fast as you can. See how size and distance affect your speed.
What you're experiencing
Fitts's Law was formulated by psychologist Paul Fitts in 1954. It predicts that the time required to move to a target is determined by:
- Target size: Larger targets are faster to hit
- Distance: Closer targets are faster to reach
The formula is: T = a + b × log₂(2D/W)
where T is time, D is distance, and W is width.
UX implications: Make important buttons larger and position them closer to where users' cursors naturally rest. This is why primary actions are often big buttons, and why mobile touch targets need to be at least 44×44 pixels.