How to Test Your Website for Accessibility: Tools and Manual Checks, Step by Step

If you want to know whether your website is truly accessible, a single tool won't cut it. Depending on the source, automated scanners catch only a fraction of the actual problems – the rest you'll uncover only through manual testing. This guide walks you through both paths: first the quick tool checks, then the manual testing that makes the difference. We don't just test accessibility on client projects; we run seven of our own brands in production – including an accessibility scanner. So the steps that follow come from hands-on practice, not a textbook.

Why Automated Tools Tell Only Half the Story

Automated testing tools are useful because they spot technical errors in seconds: missing alt text, insufficient colour contrast, unlabelled form fields, broken HTML structure. What they can't do is judge meaning. A tool can see that an image has alt text – but it has no way of knowing whether that alt text describes the image in a meaningful way. By the same token, it can't tell whether the tab order is logical or whether a video needs captions. Rule of thumb: a clean tool report doesn't mean accessible, it just means no obvious technical errors.

Step 1: A Quick Tool Check

Start with free, well-established tools. These three cover the bulk of the points that can be checked automatically:

• WAVE (wave.webaim.org) – flags errors visually right on the page, ideal for a first overview.
• axe DevTools – a browser extension for Chrome and Firefox, highly precise with few false positives.
• Lighthouse – already built into Chrome (DevTools → Lighthouse tab), giving you an accessibility score plus concrete recommendations.

Don't just check the homepage. Test at least one page of each template type: the homepage, a subpage, a form (contact or checkout), and, if you have one, a blog article. Make a note of the recurring errors – often a single cause sits in the template and affects hundreds of pages at once.

Step 2: Navigate With the Keyboard

This is the most important manual test – and it costs nothing. Click once into the address bar, then operate the entire page using only the keyboard:

• Tab moves forward, Shift+Tab moves back through all links, buttons and form fields.
• Enter and the Space bar trigger actions, and the arrow keys control dropdowns and sliders.

As you do, watch for three things: Is it always visible where you currently are (a clear focus outline)? Is the order logical and does it follow the reading flow? Can you get everywhere – and back out again – especially out of menus, pop-ups and cookie banners? If you get stuck on an element or the focus disappears, you've found a real problem that no scanner reliably reports.

Step 3: Listen With a Screen Reader

You don't need expensive software. On Windows, Narrator is built in (Ctrl+Win+Enter); NVDA is free and widely used; and on the Mac, VoiceOver is ready to go (Cmd+F5). Close your eyes and listen to how the page is read aloud. Good questions to ask:

• Are images described meaningfully – or just read out as image or by their file name?
• Are headings recognisable as headings, so you can jump between them with shortcuts?
• Are form fields clearly named (First name, Email) rather than just input field?
• Are error messages and status updates actually announced?

It feels unfamiliar at first, but even ten minutes will show you how your site sounds to blind users.

Step 4: Check Colour, Contrast and Zoom

Set your browser zoom to 200 per cent: does everything stay readable, or does text overlap and disappear behind edges? Switch temporarily to greyscale to see whether information is conveyed by colour alone – for example, red required fields with no additional asterisk or label. Check the contrast between text and background with WebAIM's contrast checker; the minimum is 4.5:1 for normal text.

What the Tools Can't Do for You

Some points call for human judgement: are link texts meaningful (more info rather than click here)? Is the language clear? Do videos have captions? These content-related questions are often the last ten per cent – and exactly the ones that determine real usability.

Honestly: for a simple, cleanly built website, steps 1 to 4 get you remarkably far, often without any outside help at all. When things get more complex – a shop, a booking system, an interactive dashboard – or when the topic is on your compliance list because of accessibility legislation, a structured audit against the WCAG criteria is worth it. We build websites and tools from the outset so that these tests pass cleanly – because fixing things after the fact is always more expensive than designing accessibility in from the start.