Hick's Law Calculator
Estimate how long users need to make a decision based on the number of choices. T = b × log₂(n + 1) – adjust the variables and see the growth curve in real time.
Decision time at 4 choices
T = 150 × log₂(4 + 1) ≈ 348ms
Within Miller's optimal range of 7 ± 2 items – comfortable.
Growth curve – 1 to 4 choices
Why Hick's Law Shapes UX Design
William Edmund Hick and Ray Hyman independently established in 1952 that decision time increases logarithmically – not linearly – with the number of choices. This is a counterintuitive finding. Doubling the number of options does not double decision time; it adds roughly one more unit of processing. The logarithmic relationship is what makes Hick's Law practical for interface design: even large menus are manageable, as long as choices are organized, predictable, and well-labeled.
In practice, every navigation menu, dropdown, toolbar, and onboarding flow is a direct application of this law. A 12-item navigation bar takes roughly 3× longer to scan than a 4-item one. A settings page with 40 options can paralyze users who came in with a clear goal. The goal of IA (information architecture) is not minimizing choices – it's minimizing the perceived effort of choosing. Grouping, visual hierarchy, defaults, and search are all strategies that manipulate the effective n the user must evaluate at any moment.
The Miller's Law warning at n > 7 connects to a separate but related finding: human working memory holds 7 ± 2 chunks simultaneously. When users must evaluate more than 7 ungrouped options, they must rely on deliberate scanning rather than pattern recognition – which is slower, more error-prone, and more fatiguing. This is why chunking navigation into logical groups (even with more total items) often outperforms flat lists. The cognitive load factor (×1.5) in this tool approximates the additional time cost when choices are unfamiliar, unlabeled, or require reading rather than recognizing.