AccessLint Core vs
Axe Core
Rocket Validator runs both accessibility engines on the same crawl. Their findings land in one report, each issue labelled with the engine that found it, so you can see exactly where they agree and where they don't.
Why run two engines
Every accessibility engine has blind spots. That is not a criticism of any particular tool, it is how automated testing works: a rule either exists or it doesn't, and no two teams have written exactly the same rules.
Axe Core checks whether your buttons are big enough to tap reliably. AccessLint Core doesn't have that rule. AccessLint Core checks whether anything you can tab to actually shows a focus outline. Axe Core doesn't have that rule.
Run one engine and you get one set of blind spots. Run both and the gaps stop overlapping.
Both engines run on the same crawl. Each issue is labelled with the engine that found it, so you can tell at a glance which findings are corroborated and which came from only one source.
The same crawl also runs W3C HTML validation, so you see the malformed markup underneath. A lot of accessibility failures are really HTML failures wearing a costume.
What this changes for you
Fewer things slip through
The issues both engines agree on are the ones you fix first. The ones only one engine found are the ones you would have missed entirely with a single-engine tool.
Scan more often
AccessLint Core is fast enough to keep up with the crawler rather than becoming the thing you wait on. On a large site that is the difference between checking everything once a quarter and checking everything every night.
Know what to do about it
Every rule in both engines has a remediation guide built into the report: what the rule checks, which WCAG criterion it maps to, and code showing the fix. Nobody has to go and interpret the spec.
Built for the sites that are hard to check
A browser extension checks the page you are looking at. That is fine for a portfolio site and useless for a 4,000-page government portal, an e-commerce catalogue, or a documentation set that three teams push to every day.
Rocket Validator crawls the site, runs your chosen engines on every page it finds, and groups the results so you fix the pattern once instead of chasing the same broken component across two hundred templates.
Which engine should I run?
Run both. They cost the same credits per check and the findings land in one report.
If you have to choose: pick Axe Core when your report has to map to a named legal framework, because every Axe rule carries Section 508, EN 301 549, RGAA and Trusted Tester tags. Pick AccessLint Core when you are scanning a very large site frequently and want the crawl to finish faster.
Axe Core
- Maintainer
- Deque Systems
- Licence
- MPL 2.0
- Rules
- ~90
- WCAG
- 2.0, 2.1, 2.2 · A, AA, AAA
- Compliance tags
- Section 508, EN 301 549, RGAA v4, Trusted Tester
- Dependencies
- Several bundled
- Runs in
- Browsers, headless
- Contrast in virtual DOM
- Not supported
- API
- Async
- Maturity
- Since 2015, industry standard
AccessLint Core
- Maintainer
- Cameron Cundiff
- Licence
- MIT
- Rules
- 95
- WCAG
- 2.2 · A, AA (+AAA contrast)
- Compliance tags
- WCAG criteria only
- Dependencies
- None
- Runs in
- Browsers, headless, happy-dom, jsdom
- Contrast in virtual DOM
- Supported
- API
- Synchronous
- Maturity
- 0.17, active development
Axe covers some things AccessLint doesn't.
The clearest gap is target-size, the WCAG 2.2
touch-target check. Axe also has rules for <select>
accessible names, tab names, autoplaying audio, and several newer ARIA attributes.
AccessLint covers a couple Axe doesn't. It flags alt text padded with filler words like "image" or "photo", and it checks that elements in the focus order have a visible focus indicator (WCAG 2.4.7), which Axe has no equivalent rule for.
Axe has the deeper compliance story. Every Axe rule is tagged with Section 508, EN 301 549, RGAA and Trusted Tester references. If your report has to map to a specific legal framework, Axe gives you that mapping directly.
AccessLint is faster and lighter. For most people that's invisible. On a 5,000-page crawl it isn't.
This mapping is by concept, based on each engine's published rule documentation. Behavioural parity between the two engines has not been independently verified.
Get started
Both accessibility engines are included on Pro, Agency and Enterprise plans, alongside W3C HTML validation. Run one or both on the same report.
Pro starts at €59/month with up to 50,000 checks, scheduled monitors, muting and device viewport emulation.
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