How are rem conversions calculated?

rem conversions assume a 16px root font size by default (the browser default). You can change this to match your project's root font size.

What is the difference between em and rem?

em is relative to the parent element's font size; rem is relative to the root element's font size. rem is more predictable for layouts.

Can I use this for viewport units?

Yes. Enter a viewport width or height to calculate vw and vh equivalents for any pixel value.

CSS Unit Converter

Convert CSS values between px, rem, em, pt, and vw units.

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About CSS Unit Converter

Convert CSS values between px, rem, em, pt, and vw units. Powered by JustUse.me — free, ad-free, and private. This tool runs entirely in your browser. Your files are never uploaded to any server.

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