"Laws of UX" are not laws in the legal sense. They are patterns about how people see, remember and decide, observed again and again. I keep eight of them in my head when I design internal tools and reporting products, because they settle arguments faster than opinions do.
Each law below has one sentence on what it says, a diagram, and what I actually do about it.
1. Fitts's Law
The time to reach a target depends on how far away it is and how big it is.
In practice
- Make primary buttons big, and keep them close to where the hand or cursor already is.
- On mobile, place frequent actions within thumb reach and keep touch targets at least 44 px.
- Don't put a destructive action right next to a safe one.
2. Hick's Law
The more choices you show, the longer people take to decide.
In practice
- Cut options, or split a long menu into steps.
- Highlight one recommended choice, as in the diagram.
- Hide rarely used actions behind a "More" menu instead of deleting them.
3. Jakob's Law
People spend most of their time on other sites, so they expect yours to work like those.
In practice
- Keep the logo top left, search where people look for it, and the cart top right.
- Spend your "novelty budget" on the product's core idea, not on the navigation.
- When you must change something familiar, give people a short, clear heads-up.
4. Miller's Law
Short-term memory holds only a small number of items at once.
Miller's famous number is seven, plus or minus two. Later research suggests the real limit may be closer to four chunks. The point is the same either way.
In practice
- Group long numbers, codes and forms into chunks.
- Don't make people remember something from one screen to use it on the next.
- Break long forms into short steps with a clear sense of progress.
5. Doherty Threshold
Productivity soars when the system responds fast enough that nobody has to wait.
The usual rule of thumb is a response within about 400 ms, from IBM research in the early 1980s.
In practice
- Respond to every tap immediately, even if the real work finishes later.
- For anything slower, show a skeleton or a progress indicator.
- Prefer showing a result that is slightly stale over making someone stare at a spinner.
6. Aesthetic-Usability Effect
People perceive attractive designs as easier to use.
This was shown in a 1990s study of ATM interfaces, where the better-looking ones were rated as easier to use even though they worked the same.
In practice
- Visual polish is part of usability, not decoration on top of it.
- Be careful, though: a pretty interface can hide real problems during testing, so test with real tasks.
7. Peak-End Rule
People judge an experience mostly by its most intense moment and by how it ends.
This comes from research by Daniel Kahneman and colleagues on how people remember experiences.
In practice
- Find the emotional high point of your flow and make it great.
- Design the last screen on purpose: a clear confirmation, a small thank-you, a next step.
- Fix the worst moment first. One bad step can colour the whole memory.
8. Law of Proximity
Elements that are close together are seen as a group.
This is one of the Gestalt principles of perception.
In practice
- Put a label closer to its own field than to the one above it.
- Use space to group related things before adding borders or background boxes.
- When a screen feels messy, adjust the spacing first.
How I use these
I treat them as a checklist, not as rules to obey. Before a design review I ask five quick questions:
- Can the main action be hit easily? (Fitts)
- Are there too many choices on this screen? (Hick, Miller)
- Does it behave like the tools people already know? (Jakob)
- Does it respond fast, or at least show progress? (Doherty)
- Is the best moment and the final moment good? (Peak-End)
If the answers are yes, the layout and polish (Proximity, Aesthetic-Usability) usually follow.
If you want the full catalogue with research references, Laws of UX by Jon Yablonski is the best place to start.
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