Design
PX ↔ REM Converter
Keep spacing scales consistent across CSS units. Processing stays on your device — no upload, no account.
How to use PX ↔ REM Converter
- Set your root font size (usually 16).
- Type a value in px, rem, or em.
- Copy the converted units.
Why use this free px to rem tool?
- All processing happens locally in your browser. Your files are never uploaded to a server.
- Live synced fields.
- Custom base size.
- Designer-friendly.
Technical details
rem uses the root size; em here assumes the same base for quick estimates (true em depends on parent font-size).
PX ↔ REM Converter FAQ
Uploaded?
No. All processing happens locally in your browser. Your files are never uploaded to a server.
Why 16px?
Common browser default — change it to match your design system.
em vs rem?
rem is root-relative; em is parent-relative — this tool approximates em with the base size.
Subpixels?
Values may round slightly for readability.
Related free converters
More private browser tools people use with px to rem.