CSS Unit Converter (px, rem, em, pt)

Convert between CSS units. Set your root font size (default 16px) to translate px ↔ rem ↔ em.

100% freeNo sign-upRuns in your browserNo upload · data stays private

📖 Read the full CSS Unit Converter (px, rem, em, pt) guide — how it works, examples & FAQ →

How to use this tool

  1. Enter a value.
  2. Pick units and root size.
  3. Read the converted value.

Example

16px → 1rem (root 16)

Why it's private

This tool runs entirely in your browser using JavaScript. Whatever you paste is processed on your own device — it is never uploaded to a server, logged, or stored. Built by Calabi, which also strips AI metadata and C2PA signals from images and video.

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