APCA (Accessible Perceptual Contrast Algorithm) is a new method for predicting contrast for use in emerging web standards (WCAG 3) for determining readability contrast. APCA is derived form the SAPC (S-LUV Advanced Predictive Color) which is an accessibility-oriented color appearance model designed for self-illuminated displays.

🅰️ Image microservice for color contrast information

A collection of useful tools for accessibility testing and debugging in the browser, online and desktop

A library to aid in using colors

Check the contrast between different colour combinations against WCAG standards

An accessibility checker tool for validating the color contrast based on WCAG 2.0 and WCAG 2.1 standards.

Inspect the contrast in color combinations, making sure to comply with the accessibility guidelines established by WCAG.

Include is a tool built to make annotating for accessibility (a11y) easier—easier for designers to spec and easier for developers to understand what is required.

Sketch Plugin to check and adjust color contrast accessibility with live preview and sliders. Endorsed by Sketch.

Un sélecteur de styles, léger et open source, pour permettre aux personnes en situation de handicap d’adapter votre site à certains de leurs besoins.

A Sketch plugin that let’s you test an entire color palette against the WCAG 2.0 contrast guidelines.

Accessibility assistant for all your basic needs. Serves as a linter for compliant color contrast and type based on WCAG 2.1. Thanks to Ale Muñoz for his support and docs!

Zero clientside JavaScript color contrast checker, built with Eleventy Serverless for the 11ties

Some useful resources for web accessibility

Yet another list of web accessibility resources

Checks the color contrast of your color design based on Web Content Accessibility Guidelines (WCAG)

🎨🧰 A versatile collection of color tools for designers and developers encapsulated in one web app - shades, tints, tones, harmonies, contrast, color blindness, gradients, and more!

Command line tool to check the contrast between two colours against WCAG standards

🎨🍭 An iOS utility framework for working with colors.

🎨 Color contrast suggestion tool, based on APCA