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px

CSS Unit Converter

Convert px, rem, em, pt, and % with configurable bases.

Enter a value in any field — the others update automatically. rem uses root font-size, em uses a base size, % needs a reference length.

px
px
px
Converted
16px · 1rem · 1em · 12pt · 16%

About CSS Unit Converter

CSS mixes absolute units (px, pt) with relative ones (rem, em, %). Turning mockup pixels into rem, or matching print pt with screen px, works best when bases are explicit. toco.tools’s CSS Unit Converter converts among px, rem, em, pt, and %. rem uses root font-size (default 16px), em uses a configurable base size, and % needs a reference length (e.g. parent width). Absolute units follow CSS: 1in = 96px, 1pt = 1/72in. Edit any field and the others update. Everything runs in your browser—nothing is uploaded.

How to use

  1. Set root, em base, and % reference if needed
  2. Enter a number in any unit field
  3. Copy the converted values

FAQ

What’s the difference between rem and em?

rem is relative to the root font-size; em is relative to the element’s (or parent’s) font-size. This tool lets you set each base separately.

How many px is 1pt?

In CSS, 1in = 96px and 1pt = 1/72in, so 1pt = 96/72 ≈ 1.333px (12pt = 16px).

What is the % reference?

Percent depends on context (parent width for width:%, parent font-size for font-size:%, etc.). Enter that length in px.

Is my input sent anywhere?

No. All processing runs in your browser; nothing is sent to toco.tools servers.