Colour-Contrast & Terminal Readability Checker

Grade two colours, a 16-colour ANSI palette, or the whole xterm-256 cube against a background. The verdict is WCAG 2, with an APCA lightness-contrast reading (Lc) beside it as a second opinion.

This is generated in browser and is not sent to pah.moi servers.

The Colour-Contrast & Terminal Readability Checker needs JavaScript to compute ratios in your browser. It is client-only. The same grading is available offline via the contrast-cli command-line tool, which also grades a whole sixteen-colour palette (--palette, against a --bg) and the entire xterm-256 cube (--256).

Building the palette itself? The Terminal Theme & ANSI Palette Designer is the other end of the same job.

About this tool1 paragraph

Colours can be hex, rgb(), hsl(), a CSS colour name, or an xterm-256 index. The verdict uses the same relative-luminance maths this site gates its own themes on.

Use it locally This tool has a native command line twin. Build contrast-cli from the site's source with:

cargo build --release --bin contrast-cli

Source and licence terms