Outrings
Accessibility, mobile and presentation

Is my website accessible? How do I check?

What automated testing can and cannot tell you, the three manual tests worth more than any tool, and where to start on a real backlog.

3 min read
Short answer

Run an automated check first — it finds missing alt text, unlabelled form fields, bad heading order and contrast problems in seconds. Then do three manual tests: navigate with the keyboard only, zoom to 200%, and listen to a screen reader. Automated tools catch roughly a third of WCAG criteria; the manual tests catch what matters most.

What automation finds

  • Images with no alt attribute.
  • Form inputs with no associated label.
  • Buttons and links with no accessible name.
  • Skipped heading levels and multiple H1s.
  • Duplicate IDs, which break label associations.
  • Missing page language.
  • Colour contrast below threshold, where it is computable.
  • Missing landmarks, iframe titles and skip links.

That is a real and useful list, and fixing it removes most of the outright barriers.

What it cannot find

Roughly two thirds of WCAG success criteria are not machine-testable. A clean automated report is where testing starts, not where it ends.

  • Whether alt text is accurate. alt="image" passes the presence check and communicates nothing.
  • Whether the focus order matches the visual order.
  • Whether an error message actually explains how to fix the error.
  • Whether a custom component behaves the way its ARIA role claims.
  • Whether video captions are correct, or auto-generated nonsense.
  • Whether the page is understandable.

The three manual tests

1. Keyboard only

Put the mouse away. Tab through the whole page.

  • Can you reach every interactive element?
  • Can you see where focus is at all times? A removed focus outline is one of the most common and most damaging faults.
  • Does the order follow the visual layout?
  • Can you escape from menus and dialogs?
  • Does anything trap focus?

2. Zoom to 200%

Browser zoom to 200%, then to 400%. Text must remain readable and nothing may be cut off or require horizontal scrolling. This is also a good mobile proxy.

3. Listen to it

Turn on VoiceOver (Cmd+F5 on macOS) or NVDA on Windows, close your eyes, and try to complete one task. Fifteen minutes of this teaches more than any report — you hear immediately when a button is announced as "button" with no name, or an image reads out a filename.

A note on colour contrast specifically: it depends on computed styles, inheritance and layering, so it can only be checked properly in a rendering engine. A tool that reports "no contrast issues" from HTML alone is reporting that it could not check, not that the page passes. Ours says requires_browser rather than claiming a pass.

Where to start on a backlog

  1. Fix keyboard access and visible focus first. Without these, some people cannot use the site at all.
  2. Add labels to every form control.
  3. Fix alt text on informative images; set alt="" on decorative ones.
  4. Fix heading structure so the page can be navigated by headings.
  5. Fix contrast.
  6. Then work through the automated report.

This is also, in most jurisdictions, a legal obligation for public bodies and increasingly for commercial sites. The stronger argument is simpler: a meaningful share of your visitors are affected, and most of these fixes take minutes.

What our audit reports about this

Every item below is measured directly, not inferred. Run it against your own site and the result names the exact rule or header responsible.

  • Sixteen accessibility checks including language, titles, alt coverage and quality, form labels, accessible names, duplicate IDs, heading order, landmarks, iframe titles and ARIA validity.
  • Whether zoom is disabled by the viewport meta tag.
  • Whether a skip link exists and whether positive tabindex values are in use.
  • Colour contrast reported as requiring a browser rather than claimed as passing.
  • An explicit statement that automated testing cannot prove conformance.

For agents and scripts, the same measurement is at /api/v1/a11y?url=yoursite.com — see the API documentation.

Related questions

Does an automated pass mean I am compliant?

No, and no honest tool will claim otherwise. Automation covers around a third of WCAG criteria. A clean report means no machine-detectable violations, which is a good start and not a conformance claim.

Which WCAG level should I target?

AA is the common legal and procurement standard, and is achievable for most sites. AAA is rarely required in full and includes criteria that are impractical for general content.

Is accessibility good for SEO?

Overlapping rather than identical. Alt text, heading structure, semantic markup and page language help both. But do it because people need it — the SEO benefit is a side effect, and treating it as the main reason leads to doing the parts that are visible to crawlers and skipping the parts that are not.

Read next

Why do my images need alt text?

Because without it, some people get nothing at all — and everything else that reads your page gets nothing either.

Read

What is a skip link and do I need one?

A hidden link that lets keyboard users jump past your navigation. Five lines of code, and without it every page starts with the same twenty tab presses.

Read

Why is my site not mobile-friendly?

The specific faults that break sites on phones — starting with the viewport tag and the tables nobody tested at 375 pixels.

Read

Why are my images missing alt text and does it matter?

It matters for people using screen readers, for image search, and for anything trying to understand your page. The fix is small and the excuses are usually wrong.

Read

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