When you need this conversion
Checking how big type will be on a printed sign, label or poster when the brief is in centimeters, or describing a font size to someone who thinks in metric. Design software sets type in points, so the conversion runs whenever a metric specification meets a point-based layout.
The exact relationship
The point used by InDesign, Illustrator, Word, PDF and CSS is defined as 1/72 of an inch, and the inch is defined as exactly 2.54 cm. So:
- 1 pt = 0.0352778 cm
- 12 pt = 0.423333 cm
- 36 pt = 1.27 cm
- 72 pt = 2.54 cm
For finer work, the points to millimeters converter gives the same values in millimeters, which is how most print specifications are written.
Font size isn’t letter height
A font size measures the em square, the invisible box each character is designed in. The visible letters are smaller. In many typefaces the capital letters are about 70% of the font size, and lowercase letters about half. So 72 pt type has a 2.54 cm em but capital letters closer to 1.8 cm. If a sign or label rule sets a minimum letter height, measure a printed sample or check the typeface’s cap height.
Common mistakes
Using a screen DPI. Points to centimeters needs no resolution setting. If a converter asks for DPI, it’s converting pixels, not points.
Mixing old point systems. Traditional printer’s points and Didot points were slightly different sizes. Everything digital uses the 1/72 inch point.
The reverse is centimeters to points.