Convert between every CSS length, angle, time and resolution unit — with a real, configurable font-size, viewport and container context, not a fixed assumption.
CSS Units lessonOne device pixel at 96dpi — the fixed reference every other length ultimately resolves against.
Rendered at the size your context settings on the right produce — not your real browser window.
16px
| Unit | Value |
|---|---|
| px | 16 |
| em | 1 |
| rem | 1 |
| % | 2 |
| ch | 2 |
| vw | 1.1111 |
| vh | 1.7778 |
| vmin | 1.7778 |
| vmax | 1.1111 |
| cqw | 4 |
| cqh | 5.3333 |
| cqi | 4 |
| cqb | 5.3333 |
| cqmin | 5.3333 |
| cqmax | 4 |
| pt | 12 |
| pc | 1 |
| in | 0.1667 |
| cm | 0.4233 |
| mm | 4.2333 |
| q | 16.9333 |
Every ratio here is a fixed CSS-spec constant (1in = 96px, 1cm = 96/2.54px, and so on) or pure percentage math against the context values below — exact by spec, the same in every standards-compliant browser. The one exception is ch: the width of the "0" character genuinely depends on the loaded font, so that ratio is measured from a real, live DOM element instead of assumed.
Measured live from this page’s own font — not a guess.
1rem