Automated vs. manual accessibility testing: what each one catches
Automated tools are fast, consistent and cheap to run every day. They also can't tell you whether your alt text is accurate or your checkout makes sense. You need both kinds of testing.
What automated testing is good at
A scanner loads your page and checks the code and the rendered result against rules that have a clear yes-or-no answer. Engines like the open-source axe-core are designed to avoid false alarms, so what they report is usually a real problem.
- Images with no text alternative at all
- Form fields with no label
- Text and background colors below the contrast ratio
- Missing page language and page title
- Buttons and links with no accessible name
- Invalid or misused ARIA
- Zoom blocked by the viewport tag
Because it's automatic, it can run on every page every day, so you hear about a new problem when a page changes, not months later.
What needs a person
Many WCAG criteria are about meaning and experience. A tool can see that something exists; it can't judge whether it's right.
- Whether alt text actually describes the image, or just says “image”
- Whether a label or link text is clear to a visitor
- Whether captions match what's said in a video
- Whether the keyboard focus order is logical and nothing traps it
- Whether headings reflect the real structure of the page
- Whether error messages explain how to fix the problem
- Whether a whole task, such as ordering or booking, can be finished with a screen reader
Why a clean scan isn't the finish line
A page with zero automated errors can still be hard to use. And a high score isn't a legal safe harbor: no tool can promise you won't receive a complaint. Treat automated results as the floor you keep clear every day, and manual checks as the way you find what the floor can't show.
A routine that works for small teams
- Run automated scans on your whole site continuously, and fix new issues as they appear.
- Once a month, pick your most important task, like ordering, booking or contacting you, and do it with only a keyboard.
- Once a quarter, try that task with a screen reader: VoiceOver is built into Macs and iPhones, and NVDA is free for Windows.
- Read your alt text and link text out loud. If it doesn't make sense without the picture or the context, rewrite it.
- Before any redesign or new feature, check it by hand before it goes live.
- Ask people with disabilities for feedback, and make it easy to report a problem.
Choosing a testing approach
- Just launched or redesigning? A one-time manual review of key templates and tasks pays off most.
- Site changes often? Continuous automated monitoring catches regressions.
- Under a legal deadline or a complaint? Get both, and talk to a lawyer.
Where Scanpoof fits
What Scanpoof does automatically
- Daily scans with the axe-core WCAG A and AA rules
- Extra checks axe leaves out, such as missing main headings, link text that points to different places and menus published as images
- A dated record of what was found and what was fixed
What still needs a person
- Judging meaning: alt text, labels, headings, captions
- Keyboard and screen reader walkthroughs of key tasks
- Feedback from people with disabilities
A free scan of one page shows the automated half in about a minute.