Conversion method
Desktop publishing/CSS conventions: 1 point = 1/72 inch; 1 pica = 12 points; 1 CSS pixel = 1/96 inch. Historical printer’s points and device pixels are not interchangeable.
px = x × 1.3333333333333335
10 pt = 13.333333 px.
| pt | px |
|---|---|
| 1 | 1.333333 |
| 5 | 6.666667 |
| 10 | 13.333333 |
| 25 | 33.333333 |
| 50 | 66.666667 |
| 100 | 133.333333 |
Unit definitions and sources
Desktop publishing/CSS conventions: 1 point = 1/72 inch; 1 pica = 12 points; 1 CSS pixel = 1/96 inch. Historical printer’s points and device pixels are not interchangeable.
| Unit and system | Use | Definition | Relationship |
|---|---|---|---|
| Point (DTP/CSS) (pt); si | Common units | Point (DTP/CSS): base (m) = value × 0.00035277777777777776. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| CSS reference pixel (px); si | Common units | CSS reference pixel: base (m) = value × 0.0002645833333333333. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Pica (DTP/CSS) (pc); si | Specialist units | Pica (DTP/CSS): base (m) = value × 0.004233333333333333. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Millimeter (mm); si | Specialist units | Millimeter: base (m) = value × 0.001. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Inch (in); si | Specialist units | Inch: base (m) = value × 0.0254. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Meter (m); si | Specialist units | Meter: base (m) = value × 1. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
| Centimeter (cm); other | Specialist units | centimeter = 0.01 m, derived from the component SI/customary definitions. Common use: Typography. Source checked 2026-09-20 (implementation review). | Exact definition; numerical display may be rounded |
Sources: W3C: CSS Values and Units: absolute lengths; NIST: SP 811 Appendix B.8: conversion factors; BIPM: SI prefixes
Precision of typography conversions
All 7 typography units convert through Meter (m). 7 have an exact defined relationship to the base unit and 0 are conventional or measured values. Results and the tables on this page come from the same engine, so a table value can be checked against the converter directly.
Standard display shows up to six decimal places, switching to scientific notation for very large or small values. Calculation uses JavaScript binary floating point independently of display rounding, so extra digits are not a claim about measurement accuracy. Each unit lists its own source; a citation records where the definition comes from, not an independent review. See Conversion methodology for the review and correction process.