px, pt, pc, in, cm, mm and Q against the spec anchor 1in = 96px, with every unit worked out in pixels and millimetres.
| Unit | As the spec defines it | Per inch | In pixels | In millimetres |
|---|---|---|---|---|
| Pixel (px) | 1px = 1/96th of 1in | 96 | 1 | 0.264583 |
| Point (pt) | 1pt = 1/72nd of 1in | 72 | 1.333333 | 0.352778 |
| Pica (pc) | 1pc = 1/6th of 1in = 12pt | 6 | 16 | 4.233333 |
| Inch (in) | 1in = 2.54cm = 96px | 1 | 96 | 25.4 |
| Centimetre (cm) | 1cm = 1/2.54th of 1in | 2.54 | 37.795276 | 10 |
| Millimetre (mm) | 1mm = 1/10th of 1cm | 25.4 | 3.779528 | 1 |
| Quarter-millimetre (Q) | 1Q = 1/40th of 1cm | 101.6 | 0.944882 | 0.25 |
CSS absolute length units, anchored to 1in = 96px by UnitGlide, reusable under CC BY 4.0.