EM / REM / PX Converter
Convert between CSS em, rem, and px with a custom base font size.
How It Works
Enter any value in px, em, or rem. The other two update instantly using the base font size (default 16px, the browser standard).
FAQ
EM vs REM?
EM is relative to the parent's font size; REM is relative to the root (html) element.
Default base?
16px — the browser standard.
Which should I use?
REM is generally preferred for predictable, accessible scaling.
Decimals?
Yes — up to 3 decimal places.
Privacy?
All math in your browser.
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