Add alt text to PDF images
Write a description of each picture into the document, where a screen reader reads it.
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Or paste them, or pick them from this device. Nothing is uploaded: the work happens in this tab.
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Each picture, and what someone who cannot see it needs to be told.
'descriptions' needs at least 1 item, but has 0.
Write the descriptions
Add a file to get started.
What this does
A screen reader reading a PDF reads its structure tree rather than its page, so a photograph with nothing said about it is silence — and a chart carrying the whole point of a report is silence with a caption underneath. Writing a description into the file fixes that for everyone who ever opens it, not just for you: the text goes onto the picture’s own element, travels with the document, and is what a reader speaks when it reaches the picture. A file that was never tagged gets the tagging it needs to hold one.
What it will not do
Every tool here says what it cannot do, in its own words, before you rely on it.
- A picture is named by the page it is first drawn on and its number among that page’s pictures — the same numbering Extract images uses, which is also how it names the files it gives you.
- A picture drawn from inside a form — a stamp, a reusable header, an imported page — is described only where the document is already tagged for it, because marking it up would mark it up everywhere the form is used.
- A picture drawn straight into the page’s instructions rather than stored as an object cannot be named or described.
- This writes what a screen reader speaks. It does not check the rest of what makes a document accessible: reading order, headings, table headers and language are untouched.
- A description is written as text on the picture’s own element. It is not drawn on the page, and nobody reading the page with their eyes will see it.
Questions people ask
How do I know which picture is which?
Run Extract images first. It names each file after the page and the number this asks for — report-3-2.png is page 3, picture 2 — so you can look at the picture you are describing.
Does this make my document accessible?
It fixes one part of it, and an important one. Reading order, headings, table headers and the document’s language are separate questions this does not touch.
Is my file uploaded anywhere?
No. The work happens in this browser tab, on your own machine. There is no server in this product to send a file to, which is why the promise is checkable rather than something you have to take on trust: open your browser's network panel and watch it do the work without making a request.
Is there a size limit, or a limit on how many files?
None that we impose. The limit is your own machine's memory, because that is where the work happens — a few hundred megabytes is comfortable on a laptop, and less on a phone. There is no daily task counter, no queue and no account.
What does it cost, and what is the catch?
Nothing, and there is no paid tier that unlocks features: the whole product is the free one. That is affordable because running it costs us nothing — your computer does the work — so there is no per-file cost to recover, no advertising and no data to sell.