An accessibility audit tells you exactly where your website fails the people who use assistive technology — and what to fix first. If you've been asked whether your site is "ADA compliant" or "WCAG compliant," an audit is how you actually find out, instead of guessing.
This guide explains what an accessibility audit is, the difference between automated and manual testing, how to run one step by step, and a checklist you can use today. It also covers when it makes sense to use an accessibility audit service instead of doing it yourself.
What is an accessibility audit?
An accessibility audit is a structured evaluation of a website, app, or document against a recognised accessibility standard — most commonly the Web Content Accessibility Guidelines (WCAG). The goal is to identify barriers that prevent people with visual, motor, auditory, or cognitive disabilities from using your content, and to document them so they can be fixed.
A good audit answers three questions:
- What's broken? The specific success criteria your pages fail (for example, low colour contrast or missing form labels).
- How bad is it? The severity and how many users or pages are affected.
- What do we fix first? A prioritised list, so your team works on high-impact issues before edge cases.
Most audits are measured against WCAG 2.1 or 2.2, Level AA — the benchmark referenced by the ADA (via US Department of Justice guidance), Section 508, and the European Accessibility Act.
Automated vs manual testing
Every thorough audit combines two methods, because neither is complete on its own.
Automated accessibility testing
Automated tools scan your HTML and CSS against WCAG rules and flag issues like missing alt text, low contrast, empty links, and invalid ARIA. They're fast, repeatable, and ideal for catching common problems across many pages. A WCAG accessibility scanner can check dozens of pages in minutes and give you a prioritised report with severity and WCAG tags.
The trade-off: automated testing reliably catches roughly a third of WCAG issues. It can't judge whether alt text is meaningful, whether reading order makes sense, or whether a keyboard user can actually complete a checkout.
Manual accessibility testing
Manual testing is where a person verifies the things machines can't — navigating the site with a keyboard only, using a screen reader (such as NVDA or VoiceOver), checking focus order, and confirming that error messages and dynamic content are announced. This is what turns a list of automated flags into a real understanding of the user experience.
The most efficient approach: run an automated scan first to catch the bulk of issues quickly, then do focused manual testing on your most important user journeys.
How to do an accessibility audit, step by step
- Define the scope. Decide which pages and templates to test. You don't need every URL — pick your highest-traffic pages plus one of each template (home, product/service, article, form, checkout).
- Choose your standard. For almost every site this is WCAG 2.2 Level AA. Use the WCAG 2.2 checklist and quick reference as your yardstick.
- Run an automated scan. Use a WCAG scanner to get a baseline across your selected pages and an overall accessibility score. This surfaces repeated, high-volume issues fast.
- Test with a keyboard. Unplug your mouse. Tab through each key page. Can you reach and operate every control? Is the focus indicator always visible? Can you escape menus and modals?
- Test with a screen reader. Navigate with NVDA (Windows) or VoiceOver (Mac). Check that images, links, headings, and form fields are announced clearly and in a logical order.
- Check colour and content. Verify text contrast (4.5:1 for normal text), that information isn't conveyed by colour alone, and that content reflows at 320px width.
- Document and prioritise. Record each issue with its WCAG success criterion, severity, and affected pages. Sort by impact so developers know what to tackle first.
- Fix, then re-test. Remediate, then re-scan and re-check. Accessibility is ongoing — schedule regular audits as your site changes.
Accessibility audit checklist
Use this condensed accessibility audit checklist for a quick pass. For the full set of criteria, see the WCAG 2.2 success criteria reference.
- Every meaningful image has descriptive alt text; decorative images are hidden from screen readers.
- Text contrast is at least 4.5:1 (3:1 for large text); UI components and graphics are at least 3:1.
- All functionality works with a keyboard, and the focus indicator is always visible.
- Headings, lists, tables, and form labels use real semantic markup — not styled text.
- Every form field has a label, and errors are identified in text with suggestions.
- Pages have unique, descriptive titles and a logical heading structure.
- Video has captions; audio has a transcript.
- Content reflows to a single column at 320px without horizontal scrolling.
- Link text makes sense out of context (avoid "click here").
- Dynamic updates and status messages are announced to assistive technology.
WCAG audits, auditors, and certification
You'll see the terms WCAG audit, WCAG compliance auditor, and WCAG certification used loosely. It's worth being clear: there is no official government "WCAG certificate." WCAG is a W3C technical standard, and conformance is a claim you make (and must be able to evidence), not a licence someone issues you.
What a credible auditor can give you is a documented conformance report — often a VPAT (Voluntary Product Accessibility Template) or an audit report mapping your site to each WCAG success criterion. That documentation is what procurement teams, legal counsel, and enterprise buyers actually ask for.
Should you use an accessibility audit service?
Doing an audit yourself is realistic for a small site and a great way to fix the majority of issues. Consider an accessibility audit service when:
- You need a formal, defensible conformance report (for legal, procurement, or a VPAT).
- Your site is large, complex, or highly interactive (web apps, checkouts, portals).
- You lack in-house screen-reader and assistive-technology testing experience.
A practical middle path many teams use: run continuous automated accessibility scans to catch and track the bulk of issues yourself, and bring in a specialist for a manual audit at key milestones.
Start your accessibility audit today
The fastest way to begin is to get a baseline. Run a free accessibility check on a page, or scan multiple pages with the Inclusense WCAG accessibility scanner to get a prioritised, WCAG-tagged report and an overall score — then work through the findings using the checklist above.
Accessibility isn't a one-time project; it's an ongoing practice. But a clear audit, repeated as your site evolves, is how you turn "we think we're compliant" into evidence you can stand behind — and a genuinely better experience for every visitor.