How to Use
Set the base font size (default 16px). Enter a value in px, rem, or em. The other units update automatically.
Frequently Asked Questions
What is the difference between rem and em?
rem is relative to the root element's font size, while em is relative to the parent element's font size.
What is the default base font size?
Most browsers default to 16px as the root font size. This tool uses 16px as the default but you can change it.
Should I use rem or px?
rem is generally preferred for responsive design as it scales with the user's font size preference. px is fixed.