Captions and PDFsMaking PDFs, documents, video and audio work for everyone

Make your files and media work for everyone

A PDF can look perfect and still fail a screen reader. A video can be clear and still lose people who can't hear it.

This guide shows how to fix both, in everyday words. Tags help screen reader users read and move around a PDF.[1] Captions give the sound as text.[2]

Read why files need care → New

A PDF page and a video, with arrows leading to a person labelled Everyone.
Files and media that everyone can use.

Three habits that fix most problems

  1. 1
    Four numbered steps. One, write with styles. Two, run the accessibility checker. Three, save as PDF with the tags option on. Four, check the PDF.
    Fix the source file first, then export, then check the PDF.

    Build the file well

    Fix the source file first, then export. The W3C says the simplest way to a correct reading order is to structure the document properly where you write it.[3]

  2. 2
    Three boxes. Captions: words on screen in the same language as the speech. Subtitles: words on screen with the speech translated into another language. Transcript: a page of text separate from the video or audio.
    Captions, subtitles and transcripts are different things.

    Put sound and pictures into words

    Captions are a text version of the speech and sounds a viewer needs.[2] Transcripts and descriptions cover the rest.

  3. 3
    Three numbered steps: run the checker, read the results, fix and run again. A note below says to check by eye what the tool cannot judge.
    A loop for checking a PDF.

    Check before you publish

    Run a checker, read the results, then look at what a tool can't judge.

Where PDFs go wrong

Making a PDF accessible with tags, reading order and bookmarks New

A PDF gets its structure from tags, which are created when it is saved as a tagged PDF.[3] This page shows what they do and how to keep the order right.

Read it →

A tree. The top box is Document. Under it are Heading 1, Paragraph, Table and Figure. Under Table are Header cell and Data cell.
Tags give a PDF a hidden outline.

Browse by kind of file

Short on time?

These two pages cover the biggest wins.

  1. 1Captions, subtitles and transcripts: what's the difference?What captions, subtitles and transcripts each are, who uses them, what a caption file looks like, and why automatic captions need a human check.
  2. 2How to check a PDF for accessibility problemsA short routine for checking a PDF with an accessibility checker, reading its results, and judging by eye what the tool can't decide.

About this guide

  • No ads, affiliate links or sponsors.
  • Facts link to the standard or help page they come from.
  • The pictures are drawn for this site.

Sources

  1. Create accessible PDFs, Microsoft Support (accessed 2026-11-10)
  2. Captions/Subtitles, W3C Web Accessibility Initiative (accessed 2026-11-10)
  3. PDF3: Ensuring correct tab and reading order in PDF documents, W3C Web Accessibility Initiative (accessed 2026-11-10)