Multi-Base Number Slider

What this is for

Every base is a different lens on the same quantity. Drag the slider once and watch decimal, hexadecimal, binary, octal, and ASCII all update at the same instant. The bit grid below lights the on-bits with their power-of-two column weights, so the relationship between bit position and digit weight is visible at a glance.

Predict, then verify. Write your prediction on paper first, then slide. The byte does not care which base you read it in; the convention does.

The headline question: what do you see here that you could not see computing by hand? A hand conversion shows the answer in one base. The slider shows it in five at the same instant. Watch how few bits light up for an everyday number like 100, and how all eight light for 255. That visual asymmetry is the entire content of "bit count" as a concept.