The APCA version, to be licensed for use with guidelines: W3/AGWG.
Some useful resources for web accessibility
Free, open-source colour contrast checker. Tests foreground/background combinations against WCAG 2.1 AA and AAA. Guarantees 5 passing suggestions.
⭐ Awesome A11Y Book & Course with interactive CodeSandboxes. Learn A11Y online with pleasure.
Browser-first design quality scanner. Opens real pages in Playwright, measures actual pixels, catches AI slop patterns. Fixes them too.
design intelligence for ai coding agents. one unified cli, 36 commands across recon, review, build, plan, ship, test, reflect, power. zero npm deps.
A multi-color contrast checker that lets you test colors across multiple backgrounds and UI contexts — not just for WCAG compliance, but for practical, system-wide accessibility.
Dependency-free color contrast checker. WCAG 2.2 AA/AAA + APCA, divergence detection, conformant color suggestions. Zero build step.
Technical responses to common misconceptions about APCA
A tool to help designers and developers choose accessible text and background color combinations that meet WCAG standards.
Create, preview, and share brand typography & color tokens with a friendly contrast checker. Vite/React + Cloudflare Worker/D1.
Draw on your live website. Freehand feedback for AI agents.
Slovenský preklad nástroja Colour Contrast Analyser (CCA) od TPGi s kompletnou slovenskou lokalizáciou UI. | Slovak translation of TPGi's Colour Contrast Analyser (CCA), an unofficial fork with full Slovak UI localization.
Retna reads a color in almost any notation, normalizes it to sRGB, and then either prints it in another color space or measures it against another color. Contrast comes from WCAG 2.x by default, and APCA is available behind a flag
A minimalist, native utility for measuring color contrast anywhere across your operating system.
The accessibility layer for AI coding agents. 24 MCP tools + 6 prompts for WCAG 2.2: static and rendered audits, contrast over images, form errors, keyboard traps, blindfold usability testing, evidence packs a human can sign. Zero deps at the core, es/en. The machine finds, the human signs.
Your clients' corporate design in one place, self-hosted: colours, fonts, logos and every version, with contrast checks, an API and MCP. Early days, ideas and feedback welcome.
WCAG 2.2 color contrast checker with automatic accessible color suggestions.
Designs that are provably not ugly. Generate a whole design system from a seed — every text pairing clears WCAG AA before you see it. Plus a GitHub Action that fails a PR on a contrast regression.
Contraste WCAG 2.2 et APCA, réparation d'un duo qui échoue à teinte égale, et échelle tonale OKLCH depuis une couleur de marque.
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