Category
Laws of UX
The cognitive and psychological laws — Hick's, Fitts's, Jakob's — that shape how people use interfaces.
22 principles
Hick's Law
The more choices you show, the longer people take to decide — and the likelier they pick nothing.
Read →Fitts's Law
The time to hit a target depends on its size and distance — small, far targets are hard to reach.
Read →Jakob's Law
Users spend most of their time on other sites, so they expect yours to work the same way.
Read →Miller's Law
Working memory holds only a handful of items — chunk information to ease the load.
Read →Von Restorff Effect
The thing that stands out from its surroundings is the thing that gets noticed and remembered.
Read →Aesthetic-Usability Effect
Attractive interfaces are perceived as easier to use, and users forgive their minor flaws.
Read →Serial Position Effect
People remember the first and last items in a list far better than those in the middle.
Read →Goal-Gradient Effect
People push harder the closer they feel to a goal — so show progress to keep them moving.
Read →Zeigarnik Effect
People remember unfinished tasks better than finished ones — open loops pull them back.
Read →Doherty Threshold
People stay engaged when a system responds in under ~400ms — past that, attention drifts.
Read →Tesler's Law (Conservation of Complexity)
Every process has an irreducible complexity — either the product absorbs it, or the user does.
Read →Law of Proximity
Things placed close together are seen as related; things spaced apart are seen as separate.
Read →Law of Similarity
Things that look alike are assumed to behave alike — appearance reads as meaning.
Read →Postel's Law (Robustness Principle)
Be liberal in what you accept from users; be precise in what you give back.
Read →Law of Common Region
Elements inside the same visible boundary are perceived as one group.
Read →Chunking
Breaking information into small, meaningful groups makes it faster to scan, understand, and remember.
Read →Law of Prägnanz (Good Form)
When faced with ambiguity, the brain resolves it toward the simplest possible interpretation — the one requiring least cognitive effort.
Read →Law of Uniform Connectedness
Elements visually connected by lines, borders, shared colour, or enclosing shapes are perceived as more related than those with no connection.
Read →Occam's Razor
Among solutions that achieve the same goal, the one with fewest elements, steps, or assumptions is preferable — complexity that doesn't earn its place should be cut.
Read →Paradox of the Active User
Users never read instructions — they start immediately and muddle through, even when reading would save them time overall.
Read →Selective Attention
Users actively filter out everything not relevant to their current goal — elements outside their attention tunnel are invisible regardless of how prominent they are.
Read →Working Memory
The brain's temporary active store holds only 4–7 chunks for 20–30 seconds — information users have to remember across steps will be forgotten unless the system carries it for them.
Read →See these principles on your own site
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