Tools
Typography calculator
Typography unit calculator
Convert between points, picas, ciceros, agates, inches and millimetres.
Used for em and rem calculations
About this tool
The typography calculator converts one measurement into ten units at once: pixels, points, picas, agates, ciceros, inches, millimetres, centimetres, em and rem. It is useful when you move a print layout to the web or the other way round, when a printer quotes measurements in picas or ciceros, or when you need to know how many millimetres a 10-point type size is.
Type the value into “Convert from” and choose its unit from the drop-down. “Converted values” shows the same measurement in every unit. Click any row to make it the source unit and carry on from there. For em and rem, set the “Base font size” first; it defaults to 16 px. Underneath there is a quick reference with the most common equivalences.
Everything is calculated in your browser and no data is sent anywhere. The tool uses the CSS convention of 96 pixels per inch and the PostScript point of 1/72 inch, so pixels here are not the physical pixels of your screen. The cicero is taken as 4.512 mm (12 Didot points). It does not work out line heights or paper sizes; there are separate tools for those on this site.
Frequently asked questions
How many millimetres is a typographic point?
A PostScript point is 1/72 of an inch, or roughly 0.3528 mm. A 12 pt type size is therefore about 4.23 mm.
What is a pica?
A pica is 12 points, or 1/6 of an inch (about 4.23 mm). Layout designers often use it to measure column widths.
How does a cicero differ from a pica?
The cicero is the traditional European unit: 12 Didot points, about 4.512 mm. It is slightly larger than the Anglo-American pica, which is about 4.233 mm.
How many pixels is 12 points?
In CSS, 12 pt is 16 px, because there are 96 px and 72 pt to the inch. The actual physical size on screen can vary with the device's pixel density.