CSS Click Chart

Rem Units

Allows you to define values relative to the root element (usually the <html> element), rather than being relative to the inherited font size (like em units).


Rem Units on W3C

Example Code

Live Demonstration

This text is set to 1.5rem. This computes to 27px, which is one and a half times 18px (the root font size).

Browser Support

Can I Use rem? Data on support for the rem-units feature across the major browsers from caniuse.com.

Tools / Polyfills

Tutorials / Articles