Free PDF accessibility checker

Check a PDF, Word or PowerPoint file against WCAG 2.1 AA and PDF/UA. Results in plain English, in seconds.

Your file goes straight to encrypted storage in the United States through a short-lived upload link.
We run the PDF/UA validation from veraPDF plus our own checks for WCAG 2.1 AA, inside an isolated processing container.
You get a summary of what failed, what passed and what needs a person to review, with the same wording Acrobat and PAC use.

Check a document

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PDF, Word (.docx) or PowerPoint (.pptx). Up to 25 pages and 10 MB free, or 50 pages and 25 MB when you sign in.

Files are deleted within 24 hours. We never use your files to train AI.

What we check

65 checks in ten plain-English topics, each mapped to WCAG 2.1 success criteria and, for PDFs, PDF/UA (ISO 14289-1).

The PDF is taggedThe file has no structure tags, so assistive technology can't tell headings, paragraphs, lists, tables or images apart.Fixed automatically
All content is tagged or marked as decorationSome text, images or drawings are outside the tag tree. Every piece of content must be either tagged (real content) or marked as an artifact (decoration).Fixed automatically
Artifacts and tagged content are kept separateSome content is marked as decoration (an artifact) inside tagged content, or tagged content sits inside an artifact.Fixed automatically
No 'suspect' tags flagThe PDF has its 'Suspects' flag turned on, which tells readers the tags may be wrong.Fixed automatically
All custom tags are mapped to standard tagsThe PDF uses custom tag names (often from Word or InDesign styles) without saying which standard tag each one means.Fixed automatically
Tag mappings are validThe role map either loops back on itself or redefines a standard tag, which isn't allowed.Fixed automatically
Tag tree is well formedSome structure elements are missing required links to their parent, or tags are nested in ways the standard doesn't allow.Fixed automatically
Lists are tagged correctlyList tags are nested incorrectly. A list (L) should hold list items (LI), and each item should hold a label (Lbl) and a body (LBody).Fixed automatically
No redundant tagsSome paragraph, span or heading tags wrap nothing useful, or wrap another tag of the same kind.Fixed automatically
Tag types match the contentSome content looks like a list, caption, note or separate paragraphs but is tagged as something else.AI suggests, you approve
PDF/UA identifier presentThe file's metadata doesn't declare that it follows PDF/UA (ISO 14289-1).Fixed automatically
Document metadata presentThe file has no XMP metadata stream, where the title and PDF/UA identifier must be stored.Fixed automatically
No technical file problemsThe file has technical issues such as an invalid header, optional-content settings without names, embedded files missing names, or reference XObjects.Fixed automatically
Security settings allow assistive technologyThe file is encrypted in a way that stops screen readers from reading its text.Fixed automatically
No other PDF/UA issuesThe validator found a PDF/UA issue we don't have a plain-English explanation for yet. The technical description is shown below.AI suggests, you approve

What a machine can't check

Every report lists these separately as “Needs review”. Software can flag them, but a person has to decide.

Reading order makes senseRead the document in the order a screen reader would (our review screen numbers it for you). Columns, sidebars and captions should come in a sensible place.
Alt text says what each image meansAlt text should give the purpose of the image in context, not just name it. Charts need the key trend and values.
Color isn't the only way information is shownCheck charts, maps and status labels. Anything shown only in color (like 'items in red are overdue') also needs text, patterns or symbols.
Instructions don't rely on shape, size or positionPhrases like 'click the round button' or 'see the box on the right' don't work for people who can't see the layout.
Link text makes sense in contextEach link should say where it goes, such as 'Apply for a permit' rather than 'click here'.
Headings and labels describe the contentEach heading should tell people what the section is about. Each form label should say what to enter.
Table headers are correctFor each table, confirm which cells are headers and that they describe the right rows or columns.
Text in images and charts has enough contrastWe check real text. Text that's part of an image or chart must be checked by eye (4.5:1 for normal text).
Changes of language are markedPassages in another language (for example a Spanish paragraph in an English notice) should be marked with that language.

Standards we test against

WCAG 2.1 Level AA, the standard in the ADA Title II rule and the HHS Section 504 rule.
PDF/UA-1 (ISO 14289-1) and the Matterhorn Protocol failure conditions, the checks PAC runs.
Where we can, each result uses the same name as Adobe Acrobat’s checker and PAC, so you recognize it.

A passing check is evidence, not a legal finding. Read about what the Title II rule requires.

Free PDF accessibility checker

Check a document

What we check

Structure & tagsHidden tags that tell assistive technology what each part of the document is.15 checks

Reading orderThe order a screen reader or keyboard follows through the document.4 checks

Headings & navigationHeadings and bookmarks that let people skim and jump around.9 checks

Images & alt textText descriptions for images, charts and other non-text content.7 checks

TablesHeader cells and table structure so data makes sense when read aloud.7 checks

Links & annotationsLinks, comments and other annotations that need to be tagged and described.6 checks

FormsFillable fields that need labels and the right tags.4 checks

Language & titleDocument title and language, so it's announced and pronounced correctly.5 checks

Fonts & textWhether the text can be read and extracted correctly.7 checks

Color & contrastWhether text stands out enough from its background.1 checks

What a machine can't check

Standards we test against