Accessibility Testing Tools (axe, WAVE, Lighthouse)

All three tools automatically check things such as missing alt text, contrast values or ARIA errors, but none of them replaces manual testing. A Deque study published in 2021, based on around 300,000 recorded issues, found that automated testing with axe-core detected up to 57% of accessibility problems — considerably more than the 20 to 30% previously assumed across the industry. That figure comes from the vendor of the tool and refers to the number of individual issues found, not to the share of success criteria covered. The remainder requires keyboard testing, screen reader checks and, ideally, feedback from users with disabilities before a website can be called accessible.