Hick's Law Formula
Predicts decision time from the number of equally likely choices.
T = b × log₂(n + 1)
Worked example: b = 200 ms and n = 7. T = 200 × log₂(8) = 600 ms.
Why it matters
It shows that doubling the options does not double the time, but it does add time.
How to use it
- Use n for the number of choices.
- Use b as a value measured from users.
- Use it to compare, rather than to promise exact times.
Example
Going from 3 options to 7 adds one more bit, or one more b of time.