PDF accessibility — PDF/UA & WCAG
Check a PDF against PDF/UA and WCAG before you publish or file it. Contrast is computed from the real graphics-state colors, and anything that needs a tagged structure the file doesn't have is reported not evaluable — never an invented pass.
PDF · multi-standard (PDF/UA-1, PDF/UA-2, WCAG 2.1/2.2, Section 508, EN 301 549) · selectable + pinnable.
Every finding maps to a named clause (a PDF/UA section or a WCAG success criterion), so a result is reproducible and defensible in an audit. The compliance modules run in a workspace — the free analyzer parses structure only.
Frequently asked questions
What is PDF/UA?
PDF/UA (ISO 14289) is the standard for accessible PDFs — a proper tag tree, logical reading order, alternative text, and other structure that assistive technology relies on. Preflight checks both PDF/UA-1 and PDF/UA-2.
What is the difference between PDF/UA and WCAG?
WCAG is the general accessibility guideline (originally for the web); PDF/UA is how those principles apply specifically to PDF. Preflight checks both, plus Section 508 and EN 301 549, so you can conform to whichever standard you are held to.
Does it need a tagged PDF?
Yes for the structure-dependent checks. An untagged PDF is reported not-evaluable for those checks, not silently failed — Preflight never invents a result.
Is this a full accessibility audit?
It is deterministic, machine-checkable conformance. Some success criteria require human judgment; Preflight flags those rather than guessing, so the result is honest about what a machine can and cannot verify.
Which file formats are supported?
PDF today (PDF/UA + WCAG). Accessibility for additional formats is on the roadmap.