HTML accessibility testing API for supplied markup
The HTML accessibility testing API scans supplied markup when no public preview URL exists or a content platform needs to check an export before publication. Local resources resolve inside an isolated browser while blocked dependencies remain visible in coverage.
For generators, CMS exports, email or content pipelines, and private preview workflows
Illustrative- Entry
- index.html
- Local CSS
- 3 resolved
- Images
- 12 resolved · 1 missing
- External calls
- blocked by default
- Profile
- wcag-2.2-aa-web@1.2.0
- Inputs
- Raw HTML · static HTML bundle
- Network
- External access off by default
- Coverage
- Missing and blocked resources stay explicit
Test an export before it becomes a public URL.
Supplied HTML follows the same scan lifecycle as a rendered page, with an input mode designed for private or generated content.
- Package
Provide markup and local assets
Send raw HTML or upload a bounded static bundle with its entry document.
- Isolate
Resolve controlled resources
Load local CSS, images, and fonts while active content and external dependencies are constrained.
- Inspect
Read findings with coverage
Separate accessibility conditions from missing-resource and reduced-coverage notices.
Keep missing resources out of the accessibility finding count.
A blocked font or unavailable stylesheet changes what can be evaluated. The API reports that limitation separately instead of turning it into a false standards outcome.
machinepartialmanualChoose the technical profile behind this capability.
Supplied HTML needs a profile that matches the intended web target. Record that selection beside the fragment and the assumptions used to render it.
Move supplied markup from isolated input to reproducible finding.
The request must declare its resource boundary before the API can return evidence another engineer can recreate.
- HTML
Supply the document
Send markup through the supported asset contract.
- Resources
Declare allowed dependencies
Keep scripts, styles, and fetch behavior bounded.
- Render
Record the resulting state
Return locators and observed browser evidence.
Preflight supplied HTML before it becomes a public page.
Test one generated HTML artifact in a free workspace, then place the API between generation and publication when its context is stable.
Automated preflight is not an accessibility certification or legal determination.