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CSS Unit Converter

Enter a value in any CSS length unit - pixels, em, rem, points, or percent - along with a base font size, and instantly see it converted across all five units. Useful for translating designs between unit systems or understanding relative sizing in CSS.

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Frequently asked questions

What is the difference between em and rem?

em is relative to the font size of its parent element (compounding when nested), while rem is always relative to the root element’s font size - rem is generally more predictable for layout.

What base font size should I use?

Use your project’s actual root font size - commonly 16px by default in most browsers.

How is pt converted?

Using the standard CSS conversion where 96px equals 72pt.

Convert CSS units instantly - free.

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