Question 1

What does this PDF accessibility checker test?

Accepted Answer

It tests the structural foundations that assistive technology depends on: whether the document has a title and a set language, whether it is a tagged PDF with a structure tree, whether the text is real extractable text rather than pictures of text, whether images are likely to carry alternative text, whether any pages are empty, and whether form fields have descriptive labels. Each result comes with the reason it matters and how to fix it in your authoring tool.

Question 2

Is a passing score the same as WCAG or PDF/UA compliance?

Accepted Answer

No, and any tool claiming a one-click compliance verdict is overstating. Full PDF/UA compliance also needs a correct reading order, meaningful heading hierarchy, table headers, colour contrast checks and human judgement about whether alt text is actually useful, things that require specialist tools like Adobe Acrobat's accessibility checker plus manual review. This checker covers the automated foundation: it catches the common structural failures that make a PDF unusable in a screen reader before you invest in a full audit.

Question 3

What is a tagged PDF and why does it matter?

Accepted Answer

Tags are invisible structure markers woven through the PDF that label every element: this is a heading, this is a paragraph, this is a list, this image has this description. A screen reader navigates by those tags. Without them it falls back to guessing the reading order from visual positions, which scrambles multi-column layouts and makes tables meaningless. Most modern tools (Word, InDesign, Google Docs export) create tagged PDFs when you choose the right export option; this checker tells you whether yours did.

Question 4

How do I fix the issues this checker finds?

Accepted Answer

Fix them in the source document, not the PDF. In Microsoft Word: set the document title under File, Properties; set the language under Review, Language; add alt text by right-clicking each image; use the built-in heading styles; then export with the "Document structure tags for accessibility" option enabled. In InDesign, use the Articles panel for reading order and export a tagged PDF. Re-run this checker on the new export to confirm the fixes landed.

Question 5

Why does my scanned PDF fail the text check?

Accepted Answer

A scan is a photograph of a page. If nobody ran OCR on it, the file contains no text at all: a screen reader finds literally nothing to read, search finds nothing, and copy-paste returns nothing. Run the scan through an OCR tool to add a hidden text layer, then check it again. The scan will still need tags and a title for a good score, which the OCR or export step can add.

Question 6

Is my document uploaded anywhere?

Accepted Answer

No. The file is analysed entirely in your browser. That matters for accessibility work in particular, because the documents that most need checking, HR files, medical guidance, student materials, legal notices, are often sensitive. Nothing is sent to a server, stored or shared.

PDF Accessibility Checker

Use PDF Accessibility Checker

How to use the PDF Accessibility Checker

Upload the PDF

Read the results

Fix in the source

Re-check the export

About the PDF Accessibility Checker