automatica11y.

Test and compare the accessibility of web pages, Storybook builds, and npm component libraries.

automatica11y answers two questions:

• How accessible is this? (audit)
• How do these compare? (compare, two or more targets)

It's not an attestation or certification tool. Automated checks cover only part of WCAG, so a report says "no automated violations found" only where an engine found none, and never says "accessible." See Limits.

Install.

You need Node 20 or newer and Chrome or Chromium.

Install it once, and automatica11y is on your PATH, with the short name a11y too:

npm i -g automatica11y

You can skip the install and put npx in front of every command instead, for example npx automatica11y doctor. npx fetches the tool the first time and checks the registry after that. A global install doesn't update itself, so run npm i -g automatica11y@latest to upgrade, and automatica11y --version to see what you have. These docs write the short form. Add npx if you didn't install it.

Quick start.

automatica11y doctor
automatica11y audit https://example.com
automatica11y compare radix=npm:@radix-ui/react-dialog aria=npm:react-aria-components

doctor checks your setup. If it can't find a browser, it prints the command that installs one:

npx playwright-core install --only-shell chromium

Each run writes a folder (./a11y-report by default) with report.md, results.json, and plan.json. Reading a report explains what's in them.

Where to go next.

• Targets: what you can point it at, including one entry of an npm package.
• What it checks: the five tiers, and what each one can and can't see.
• Options and exit codes: every flag, the exit codes, and how to use it in CI.
• Reading a report: coverage, statuses, and how much to trust each result.
• npm packages and fixtures: how component libraries get tested.
• Writing fixtures: the contract for a fixture you write yourself.
• Using it with an AI agent: skills, AGENTS.md, and the guide commands.
• The agent steps: the full steps an agent follows, word for word.
• Limits: what automated checks can't tell you.