Making PDFs Accessible: What It Actually Takes

Whoever invented the habit of exporting a complex Excel spreadsheet to PDF and uploading it to a website owes a debt to every screen reader user who's encountered the result. PDFs can be done right. Most aren't.

Why Most PDFs Fail Screen Readers

Printing to PDF creates a flat image of a document — no text, no structure, just pixels. Screen readers can't read images unless OCR is applied. Even 'save as PDF' from Word creates a PDF without proper tag structure if the source document uses manual formatting instead of styles.

The result: a screen reader user encounters a PDF, hears 'document' and then nothing, or gets a wall of text with no headings, no logical reading order, and no way to navigate.

The Right Starting Point: Source Document Structure

Accessibility is much easier to build in than to retrofit. In Microsoft Word:

• Use Heading 1, Heading 2, Heading 3 styles — not bold + font size changes
• Use actual List styles — not manual bullet characters
• Add alt text to every meaningful image (right-click image → Edit Alt Text)
• Use descriptive link text — 'Download the annual report' not 'Click here'
• Run the Word Accessibility Checker before export

What 'Tagged PDF' Means

Tags are metadata embedded in the PDF that describe its structure to assistive technology. A paragraph tag tells the screen reader 'this is body text.' An h1 tag means 'this is the main heading.' An image tag with alt text tells the screen reader what the image shows.

Without tags, screen readers have no way to understand document structure. The text is present but there's no semantic meaning — it's like reading HTML with all the tags stripped out.

Testing PDF Accessibility

Adobe Acrobat Pro's Accessibility Checker is the quickest automated check. For manual testing, install NVDA (free on Windows) and navigate the PDF using only the keyboard. Try to navigate by headings (H key in NVDA). Try to read the alt text of an image. Try to submit a form using only Tab and Enter. What you encounter is what users with visual impairments experience.