Why did the UK government create the world’s least accessible web page?

Back in 2017, the UK Government Digital Services (GDS) intentionally created a single web page with over 140 unique accessibility failures. Affectionately dubbed the world’s least accessible web page.

Why? Their goal was to test the effectiveness of automated testing tools and identify if any were a reliable solution for accessibility testing at scale. They selected 10 automated tools and ran each one against the page to see how many of the failures it could identify and how many it would miss.

Their findings showed that 29% of accessibility barriers were not identified by any of the 10 tools tested. The tool with the highest accuracy was Tenon (acquired by Level Access, 2021), which returned 37% of the errors. The tool with the lowest accuracy was Google Lighthouse, which only picked up 17% of the errors.

While automated accessibility testing has improved since 2017, even today’s best tools still only catch 30-40% of WCAG success criteria. Automated tools are super useful, but they should be used in tandem with manual testing to ensure your website is fully accessible.

Automated tools are essential for catching common issues quickly. But they should be used in tandem with manual testing to ensure your website is fully accessible.

Manual testing catches what the robots miss.