PX to REM Converter
Convert between pixels, rem and em using any root font size.
How to use
Convert CSS units
Enter a value, choose its unit and set the root font size. The tool shows the equivalent value in pixels, rem and em.
- Enter a number.
- Choose px, rem or em as the input unit.
- Set the root font size and copy the result.
Root font size
Browsers default to 16px, but users and CSS can change it. Set the root size to match the project you are working on.
Frequently asked questions
Are rem and em the same here?
For the root element they are identical. The converter treats em as relative to the configured root size for simplicity.
Why use rem?
Rem units scale with the user's root font size, which improves accessibility compared with fixed pixels.
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