Free Accessibility Checker

The Accessibility Checker is a free online tool that evaluates your website against WCAG accessibility guidelines and identifies issues for users with disabilities.

Yes, it is completely free with no registration required.

The Accessibility Checker tests against WCAG 2.1 guidelines covering perceivability, operability, understandability, and robustness of your web content.

Absolutely. The Accessibility Checker processes everything client-side in your browser. No data is uploaded to or stored on any server. Your content remains private on your device at all times.

Yes, the Accessibility Checker is fully responsive and works on smartphones and tablets. You can use it on any device with a modern web browser -- no app download required.

No account or registration is needed. Simply open the Accessibility Checker in your browser and start using it immediately. There are no sign-up walls or usage restrictions.

Simply enter your input in the provided field, adjust any settings to your preference, and the tool will process it instantly. You can then copy the result to your clipboard or download it.

The Accessibility Checker works in all modern browsers including Chrome, Firefox, Safari, Edge, and Opera. For the best experience, use the latest version of your preferred browser.

An error marks a problem that almost certainly blocks someone using assistive technology, such as an image with no alt attribute, a form input with no associated label, or a missing page title. These violate a specific WCAG success criterion and weigh most heavily on your score. A warning flags something that may be a problem but needs human judgment — an empty alt that might be intentional for a decorative image, or inline text and background colors whose contrast ratio you still need to verify. Informational notes point out best practices like adding a skip-navigation link. Because an A grade requires both a high score and zero errors, fixing every error should be your first priority. Paste your HTML to see each finding sorted by severity with a recommended fix and a copy-ready code example.

The audit checks heading structure, not just whether a heading exists. It flags skipped levels — for example jumping straight from an h2 to an h4 — because screen reader users rely on a logical heading outline to navigate, and a gap suggests a missing section level. It also reports empty headings that contain no text and pages with no heading at all. These map to WCAG 1.3.1, which requires that structure conveyed visually is also available programmatically. Headings should descend one level at a time and describe the content beneath them rather than being chosen for their visual size, which you control with CSS instead. Keeping a clean outline also helps SEO, since search engines read the same hierarchy. Paste your markup and open the Headings tab to see exactly which levels are skipped or empty.

Automated tools reliably catch structural and attribute-level problems — missing alt attributes, unlabeled form fields, absent landmarks, a missing lang attribute, vague link text — which together account for a large share of real-world failures. This checker uses pattern matching on the HTML you paste, so it is fast and private but cannot judge meaning. It cannot tell whether your alt text actually describes the image, whether reading order makes sense, or measure rendered color contrast on a live page, which is why color findings are warnings asking you to verify. No automated tool catches every issue; studies generally credit them with finding only a portion of accessibility barriers. Treat a clean result as a strong first pass, then confirm with a screen reader, keyboard-only testing, and a runtime tool such as axe or Lighthouse. Run your markup here to clear the structural problems first.

Yes, and that is exactly what this tool is built for. Rather than crawling a published URL, it analyzes a block of HTML you paste in directly, so you can audit staging markup, an internal template, or a component you have not deployed yet. Because the entire analysis runs in your browser, nothing you paste leaves your device, which makes it safe for unreleased code. To use it, copy the rendered HTML from your editor or browser dev tools, paste it into the input, and run the audit. You will get an overall score, a letter grade, and findings grouped into seven categories — Images, Forms, Links, Headings, ARIA, Color, and Structure — each tied to a WCAG criterion. This lets you catch issues during development instead of after launch. Load the built-in example first to see the kinds of problems it surfaces, then paste your own.

After the audit runs you get an overall score from 0 to 100 and a letter grade from A to F, shown alongside counts of errors, warnings, and informational notes plus how many checks passed. Errors carry the most weight because they represent confirmed barriers, so a single missing alt attribute or unlabeled input pulls the score down more than a warning does. The grade reflects both the score and the error count: an A requires a high score and zero errors, meaning you cannot earn top marks while any blocking issue remains. This design pushes you to resolve real failures rather than chase a number. You can filter findings by severity or jump between category tabs, and the Export Report button downloads a plain-text summary to attach to a ticket. Paste your HTML to see your current score and exactly which fixes will raise it.