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Percent to EM Converter

Convert CSS percent values to EM units. For font-size, percent and EM are equivalent: 100% = 1em, 150% = 1.5em, 75% = 0.75em.

Last updated: May 21, 2026

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What is Percent to EM Converter?

For the `font-size` CSS property, percent and em are numerically equivalent — both relative to the parent element's font size. The conversion is: **em = % ÷ 100**.

This is useful when refactoring a stylesheet from percent-based font sizes to em units, or when working with older CSS that uses percent and you need the em equivalent.

How to Use Percent to EM Converter

1

Enter one or more percent values (comma or newline separated)

2

Copy the EM output or use the reference table

3

The formula is always: em = % ÷ 100

Common Use Cases

  • Developers converting legacy percent-based font sizes to em units.
  • Front-end engineers refactoring old stylesheets to use em for typography.
  • Teams migrating from percent to em as part of a design system overhaul.
  • Students learning the equivalence between percent and em for font-size.

Example Input and Output

Convert common percent font sizes to their EM equivalents.

Percent values
75
100
125
150
EM output
75% → 0.75em
100% → 1em
125% → 1.25em
150% → 1.5em

Privacy

All conversions run in your browser. No data is sent to any server.

Frequently Asked Questions

Is 100% always 1em?
For font-size, yes — 100% = 1em is always true because both units are relative to the parent's font size by the same factor.
When is percent preferred over em?
In practice, em is used more in modern CSS. Percent was common in older code and is still found in many legacy stylesheets. Both are valid for font-size.

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