Pa11y vs WAVE

Free and open source

From $0.04 per page (API, indicative)

Free and open source. You pay in engineering time and CI minutes.

Free for interactive use; the API is priced per page for bulk scanning.

Everything, self-hosted

Browser extension and single-page online checker are free.

Established

OSS community · since 2013

Widely used

WebAIM (Utah State University) · since 2001

• Free, scriptable and trivially added as a CI gate.
• Tests a sitemap of URLs in one run, unlike page-by-page extensions.
• Self-hosted dashboard for tracking without a vendor.

• The in-page visual overlay teaches non-specialists what is wrong far better than a list.
• Free for everyday developer and designer use.
• WebAIM's guidance behind each rule is authoritative and clear.

• No guided manual testing or remediation workflow.
• Testing authenticated or interactive states requires scripting actions.
• Maintenance activity has been intermittent.

• Manual, page-by-page — not a CI tool.
• Alerts require human judgement, so counts are not directly comparable between pages.
• No issue tracking or programme management.

Teams wanting free automated accessibility gates across many pages.

Designers and developers learning accessibility, and quick manual spot checks.