axe vs pa11y vs Lighthouse

These tools overlap, but they differ in rulesets, reporting, and what they emphasize. Combining engines improves coverage and reduces blind spots.

axe

  • Strong rules coverage for common WCAG failures
  • Widely used in dev tooling and CI pipelines

pa11y

  • Good for scripted checks and configurable thresholds
  • Works well in automated workflows

Lighthouse

  • Browser-based auditing with broader quality context
  • Helpful alongside performance and best-practice checks

Why combine them

  • Different implementations catch different patterns
  • Cross-validation helps reduce false positives
  • Better coverage for dynamic pages and templates