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CSS Unit Converter

Convert between CSS units — px, rem, em, and pt — with configurable base font sizes. See all conversions instantly as you type. Runs entirely in your browser — your data never leaves your machine.

css units px rem em pt converter frontend developer-tools

Published May 28, 2026

All interactive tools run entirely in your browser. Your data never leaves your device.

How It Works

Enter a value in any supported unit and see instant conversions to all other units. Adjust the root and parent font sizes to match your project’s typography settings — rem conversions use the root size, em conversions use the parent size.

Features

  • Four units: Pixels (px), Root EM (rem), EM (em), Points (pt)
  • Configurable base sizes: set root and parent font sizes to match your project
  • Live conversion: results update as you type
  • Copy with unit: copies value + unit suffix (e.g., 1rem)
  • Private: runs entirely in the browser — no network requests

Common Conversions (16px base)

pxremempt
120.750.759
140.8750.87510.5
161112
181.1251.12513.5
201.251.2515
241.51.518
322224

Use Cases

  • Converting pixel-based designs to rem-based CSS
  • Calculating em values for component-level typography
  • Converting between screen (px) and print (pt) units
  • Verifying responsive typography scales