What are the Laws of UX?
The Laws of UX are a collection of psychology principles applied to interface design, curated by Jon Yablonski. They are not absolute rules, but best practices based on decades of research into how humans perceive, process, and interact with digital interfaces.
For AI products —where cognitive load is already high due to technological novelty— applying these laws is even more critical. An interface that requires learning new mental models, processing too many options, or remembering information across steps will frustrate the user no matter how good the AI model is.
The 3 Foundational Laws of Interaction
1. Fitts's Law — Size and Distance
The time to acquire a target depends on the distance to the target and its size.
- Touch targets minimum 44×44px on mobile, 48×48px recommended
- Critical elements in easily accessible areas (corners, edges)
- The primary action button must be the largest visible
- Space between related elements to prevent accidental clicks
2. Hick's Law — Fewer Choices, Better Decisions
Decision time increases with the number and complexity of choices.
- Maximum 5-7 options per screen or section
- Break complex processes into steps
- Highlight the recommended option visually
- Progressive onboarding: don't show everything at once
3. Jakob's Law — Consistency with the Familiar
Users prefer your site to work like the sites they already know.
- Chat-style patterns are now the standard — leverage them
- Icons and naming consistent with known platforms
- Familiar metaphors reduce the learning curve
- Allow using the previous version for a time when making changes
For the full list of 26 laws with detailed AI applications, check the Spanish version.