Guide
Type sizes in print and on the web
The point is the classic unit of print, the pixel that of the web. Both refer to an inch, but with different denominators — which is why type in pt is not the same size as type in px.
Two inch references
A DTP point is the 72nd part of an inch. A CSS pixel is the 96th part. It follows that 1 pt = 96/72 px = 1.3333 px and conversely 1 px = 0.75 pt. Twelve points on the web are therefore sixteen pixels.
Pica and millimetre
Twelve points make one pica, 72 points one inch. An inch is exactly 25.4 millimetres, so a point is about 0.3528 millimetres. Print artwork therefore states sizes in points or millimetres, the web in pixels or relative units.
Why a pixel is not an absolute size
The CSS pixel is a reference length, not a screen cell. Browsers and operating systems scale it: zoom level, the system font-size setting and the pixel density of the device all change how large type actually appears. So 12 pt = 16 px only holds at 100 percent zoom and with an unchanged system setting.
Relative units for accessible typography
Because absolute pixel sizes can override the user setting, accessible typography works with relative units: em refers to the parent element font size, rem to the document root. A size given in rem stays scalable when someone increases the default font size in the browser. A minimum size covering all levels of vision cannot be derived from that.
Matching conversions
Matching tables
Unit family: Typography
Common questions
How many pixels is 12 pt?
16 px, calculated as 12 × 96/72.
How many pt is 16 px?
12 pt, calculated as 16 × 0.75.
Why is 1 pt not 1 px?
Because the point is defined as 1/72 inch and the CSS pixel as 1/96 inch.
Are 72 pt one inch?
In print, yes. On the web 72 pt equals 96 px.
Sources
Do not use as the sole basis for official, medical, safety-critical or contractual decisions.
Citation note: UnitCloud, guide, sources reviewed: September 2026. Source basis: W3C CSS Values and Units · NIST Guide to SI Appendix B.