Laws of UX
Fitts's Law
The time to hit a target depends on its size and its distance from the pointer or thumb.
Why it matters
Time to hit a target depends on its size and distance. Bigger, closer buttons are faster to hit, which is why primary CTAs should be large and near the user's focus.
How to apply it
- Make primary buttons large, and full width on mobile
- Place actions next to the content they act on
- Use screen edges and corners for key desktop controls
Common mistakes
- Tiny icon-only buttons
- Destructive actions right next to common ones
Quick answers
What is Fitts's Law?
The time to hit a target depends on its size and its distance from the pointer or thumb. Time to hit a target depends on its size and distance. Bigger, closer buttons are faster to hit, which is why primary CTAs should be large and near the user's focus.
How do I apply Fitts's Law in UI design?
Make primary buttons large, and full width on mobile. Place actions next to the content they act on. Use screen edges and corners for key desktop controls.
What are common mistakes with Fitts's Law?
Tiny icon-only buttons. Destructive actions right next to common ones.