Hick's Law: How to Speed Up User Decisions Through Design
Hick's Law states that decision time grows logarithmically with the number of choices. Discover practical techniques to reduce cognitive friction, simplify navigation, and help users decide faster.
What Is Hick's Law?
Hick's Law (formally the Hick-Hyman Law) states that the time it takes a person to make a decision grows logarithmically with the number of choices available. Formulated by psychologists William Edmund Hick and Ray Hyman in 1952, it is one of the most directly applicable principles in all of interaction design.
"The time it takes to make a decision increases with the number and complexity of choices available."— Hick's Law / Laws of UX
The formula: T = b × log₂(n + 1), where T is decision time, n is the number of choices, and b is a constant derived from the task. In plain English: doubling your options doesn't double decision time — but it adds a consistent, measurable cognitive cost.
Decision time grows logarithmically with the number of options — this is Hick's Law visualised. Even going from 2 to 4 choices adds measurable cognitive cost.
Why Designers Must Care
- Navigation menus with 10+ options force users to scan, compare, and second-guess.
- Product pages with too many CTAs create decision paralysis — users leave instead of choosing.
- Onboarding flows with too many configuration steps cause abandonment before value is delivered.
- The 2000 Jam Study (Iyengar & Lepper) famously showed 24 jam varieties generated more interest but 10 times fewer purchases than 6 varieties — a real-world Hick's Law demonstration.
How to Apply Hick's Law
- Minimise navigation options: 5–7 primary nav items is a proven sweet spot. Use progressive disclosure for depth.
- One primary CTA per screen: If a user can only do one important thing, make it visually dominant and singular.
- Categorise before listing: Group 20 items into 4 categories of 5 — users read the group label first and skip irrelevant branches entirely.
- Highlight a recommended option: "Most popular" or "Best for most people" labels pre-decide for hesitant users.
- Progressive onboarding: Introduce features over time rather than exposing all controls on day one.
Real-World Examples
Apple TV Remote: Went from 78 buttons (original Siri Remote) to a simplified 6-button layout — a direct application of Hick's Law resulting in far fewer support queries. Google Search: A single input field on an otherwise empty page removes every competing decision.
Key Takeaways
- More choices = slower decisions = higher abandonment risk.
- Categorisation and grouping reduce apparent choice without removing capability.
- A recommended default converts hesitant users without restricting power users.
- Apply Hick's Law hardest at friction-critical moments: checkout, sign-up, navigation.
