S
SnapUtilsPro
Design

CSS Unit Converter

Convert CSS lengths between pixels, rem, em, and percentages using your root and parent font sizes. Copy values for responsive stylesheets without mental math.

Runs entirely in your browser. Your data never leaves this device.

  • px ↔ rem ↔ em
  • Percent support
  • Root font size
  • Parent size for em
  • Copy values
Workspace
Client-side · No upload

How it works

  1. Enter a value and unit.
  2. Set root (and parent) font size.
  3. Read converted px/rem/em/% outputs.

Key features

  • px ↔ rem ↔ em
  • Percent support
  • Root font size
  • Parent size for em
  • Copy values

FAQ

Default root?

16px is the common browser default — change it to match your project.

Percent of what?

Percent conversions use the parent size you provide.

Private?

Yes.

Viewport units?

MVP focuses on px/rem/em/%; vw/vh may come later.

Keep building

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