PDF/UA

PDF/UA — short for PDF/Universal Accessibility — is the technical standard for accessible PDF documents, published as ISO 14289. Where WCAG governs accessibility on the web, PDF/UA defines what a PDF must contain to be usable by people relying on assistive technology, regardless of how the file was produced.

Test a PDF

EqualWeb’s PDF accessibility checker inspects a document’s tag tree and reading order against PDF/UA.

What it is

PDF/UA is the ISO standard that says how to make a PDF accessible. The established version is PDF/UA-1 (ISO 14289-1); a newer PDF/UA-2 builds on the PDF 2.0 file format. At its heart, a conforming document carries a correct tag tree — a logical structure that describes headings, paragraphs, lists, tables, and figures — rather than just a flat page of glyphs. From that structure, assistive technology can derive meaning, navigation, and a reliable reading order.

Concretely, a PDF/UA document provides a defined reading order, real selectable text (not a scanned image of text), text alternatives for figures, table header semantics, a declared document language, and bookmarks for long documents so readers can move through the content.

Who must comply

PDF/UA is a vendor-neutral ISO standard, not a law in itself, so it binds whoever a regulation or contract points at it. In practice that means organisations that publish documents as PDFs — public bodies, regulated industries, publishers, and their suppliers — wherever an accessibility obligation extends to documents and not only to web pages. Because PDF/UA is referenced by EN 301 549 (the European harmonised standard) and by Section 508 (US federal ICT), entities already subject to those frameworks meet their document-accessibility duty by conforming to PDF/UA.

Relationship to WCAG

PDF/UA does not replace WCAG — it complements it for the document format. WCAG is written around web content; PDF/UA translates the same underlying ideas (perceivable structure, text alternatives, reading order, language, navigation) into the requirements of the PDF file format. The two are designed to work together: applying PDF/UA is how you satisfy WCAG's success criteria inside a PDF, which is why EN 301 549 and Section 508 reference PDF/UA alongside WCAG rather than instead of it.

Key points

  • PDF/UA stands for PDF/Universal Accessibility and is published as ISO 14289.
  • PDF/UA-1 (ISO 14289-1) is the established version; PDF/UA-2 builds on PDF 2.0.
  • A conforming file needs a correct tag tree (logical structure) and a defined reading order.
  • Text must be real, selectable text — not a scanned image of a page.
  • Figures need text alternatives, and tables need proper header semantics.
  • The document language must be declared, and long documents need bookmarks.
  • It complements WCAG for documents and is referenced by EN 301 549 and Section 508.

To go deeper, pair this reference with the Learn pages on the shared technical core and on producing accessible PDFs in practice:

  • WCAG — the shared technical core that PDF/UA complements for documents.
  • Accessible PDFs — a hands-on lesson on tagging, reading order, and text alternatives in real files.

Part of a bigger picture

PDF/UA is one of several standards covered in the Standards overview. Most of them share the same technical core: WCAG. Conform to that core and you satisfy the document, web, and procurement standards that reference it.