ToolHub

CSS Unit Converter

Convert between px, rem, em, pt, and % based on a root font size. Handy for responsive typography. Everything runs in your browser.

Input
Output

Enter a value to convert

FAQ

What is the difference between rem and em?

rem is relative to the root (html) font size while em is relative to the parent element. This converter applies your base size to both.

Why is the base font size 16px?

Most browsers default to 16px. If your html element sets a different size, change the base value accordingly.

How is pt converted?

Using the CSS standard ratio of 1pt = 96/72px (4/3px), commonly used in print stylesheets.

Related tools