Imagine using a screen reader to get through a website that wasn’t built with accessibility in mind. The images have no text alternatives, and every link just says “click here.” Now imagine reading the same site with low vision, squinting at small gray text that barely stands out from its background. Good web accessibility testing tools let you catch those problems before your visitors do.
And there are a lot of visitors to think about. Pew Research found that 96% of US adults use the internet (2025), and the CDC reports that 28.7% of US adults, more than one in four, live with a disability. The standard most sites are measured against is the Web Content Accessibility Guidelines, now at WCAG 2.2 (published October 2023). Here are the tools we reach for, all free unless noted.
Automated checkers: find the obvious problems fast
WAVE
WAVE, from WebAIM, is a free browser extension for Chrome, Firefox, and Edge. Run it on any page and it marks up the page itself with icons for missing alt text, empty links, low-contrast text, missing form labels, and heading-order problems. It’s the easiest place to start because you can see each issue in context instead of reading a report.
axe DevTools
axe DevTools, from Deque, adds an accessibility tab to your browser’s developer tools in Chrome, Edge, and Firefox. The free version scans a page against WCAG rules and explains each failure with the code involved and how to fix it. It has a reputation for few false positives, which saves developers time. There’s a paid Pro tier with guided tests, but the free extension covers most needs.
Lighthouse
Lighthouse is already built into Chrome’s developer tools. Its accessibility audit runs on the same axe-core engine and gives each page a score out of 100. The score is a handy way to track a site over time, but treat it as a floor, not a finish line: a perfect 100 only means the automated checks passed.
Accessibility Insights for Web
Accessibility Insights for Web, from Microsoft, is a free extension for Chrome and Edge. Its FastPass runs automated checks and then visually shows the order a keyboard user tabs through the page, which catches problems no scanner can. Its Assessment mode walks you through a full manual review step by step.
Screen readers: hear what your visitors hear
Automated tools can’t tell you whether a page makes sense when it’s read aloud. For that, use a screen reader yourself.
NVDA
NVDA is a free, open source screen reader for Windows (donations welcome) and one of the most widely used. It can run from a USB drive, so you can use it on a computer that isn’t yours.
VoiceOver
VoiceOver comes built into every Mac, iPhone, and iPad. Testing your site with VoiceOver on a phone is one of the fastest ways to find out how it works for blind mobile users.
Simulators: see the page through someone else’s eyes
Funkify (paid)
Funkify is a browser extension that simulates dyslexia, color blindness, tremors, and other disabilities right on the page you are looking at. It now runs on paid plans after a seven-day free trial. It’s less a testing tool than an empathy tool, and it’s good at convincing a team that the problems are real.
What the tools won’t catch
Automated checkers are fast, but they can only test what a machine can measure. They can tell you an image has no alt text. They can’t tell you the alt text says “image123.jpg” or describes the wrong thing. They can’t judge whether your link text makes sense out of context, or whether a form is confusing. So use the automated tools to clear the obvious issues, then test with a keyboard and a screen reader before you call a page done.
Trying to experience the web from a different vantage point is one of the best ways to design for it. If you’d like a second set of eyes on your site, E11 offers accessibility monitoring and audits, and our post on why web accessibility is about 16% of your audience makes the case for why it matters.
