PX to REM Converter
Convert px to rem (and back) for CSS.
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About the PX to REM Converter
Convert px to rem and rem to px free, for responsive, accessible CSS. Set your root font size (16px by default), type a pixel value to get the rem equivalent, or a rem value to get pixels — the conversion is instant and works both ways. Includes a quick reference table of common sizes. Using rem instead of hard-coded pixels lets your whole layout scale with the user's browser font-size setting, which is better for accessibility.
How to use the PX to REM Converter
- 01Set your root font size (usually 16px).
- 02Enter a px value to get rem, or a rem value to get px.
- 03Copy any value from the reference table.
Frequently asked questions
What is 1rem in px?
1rem equals the root font size — 16px by default in every browser, so 1rem = 16px unless you change the root size.
Why use rem instead of px?
rem scales with the user's browser font-size preference, so text and spacing stay proportional and accessible; fixed px ignores that setting.
How do I convert px to rem?
Divide the pixel value by the root font size — 24px ÷ 16 = 1.5rem. This tool does it instantly for any root size.