WAVE vs Pa11y
Feature checklists rarely decide anything. What decides it is the pricing metric, who has to write the tests, and which limitation you can live with.
Entry price
From $0.04 per credit (one basic page scan), falling to $0.025 at 10k+
Free tierFree and open source
Open sourceWhat drives the bill
The metric that actually scales your invoice.
Free for interactive use. The API is bought in credits — one credit per basic page scan, 2-3 for advanced requests — at $0.04 each up to 999, $0.03 to 9,999 and $0.025 beyond. Minimum purchase is 250 credits ($10), and new accounts get 100 free.
Free and open source. You pay in engineering time and CI minutes.
Free tier
Browser extension and single-page online checker are free.
Everything, self-hosted
Open source
LGPL-3.0
Self-hostable
No-code authoring
Languages
Platforms
Fits teams
Adoption
Widely used
WebAIM (Utah State University) · since 2001
Established
OSS community · since 2013
Strengths
- 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.
- 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.
Limitations
- 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.
- No guided manual testing or remediation workflow.
- Testing authenticated or interactive states requires scripting actions.
- Maintenance activity has been intermittent.
Best for
Designers and developers learning accessibility, and quick manual spot checks.
Teams wanting free automated accessibility gates across many pages.
Pricing last reviewed August 2026 and is indicative only — confirm on each vendor’s own page.