CSS and design
PX to REM Converter
Convert pixels to rem units (and back) using your root font size, one value or a whole stylesheet at a time.
- Runs in your browser
- Instant results
- Free, no sign-up
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How to use the PX to REM Converter
- Set the root font size (16px by default).
- Type a value in px or rem to convert it.
- Paste CSS to convert every px value to rem at once.
Frequently asked questions
Why use rem instead of px?
rem scales with the user's browser font size, which improves accessibility and keeps spacing consistent.
What is the default root font size?
Most browsers use 16px, so 1rem = 16px unless your CSS changes the html font size.
Why are 1px borders kept?
Hairline values like 1px borders usually should not scale, so bulk conversion leaves values of 1px or less alone.