Alt Text in Translation: The Accessibility Step Everyone Skips

Here is a failure we find in almost every multilingual document set we are handed: the document has been translated properly, the text reads well, the language is even declared correctly — and every image description is still in English.

A Spanish-speaking screen reader user reaches a diagram in your Spanish form and hears an English sentence. Not a translation problem in the usual sense. The translation was fine. The alt text was never part of it.

Why does this happen so consistently?

Because alt text is not text, structurally. It is metadata attached to an object.

Translation workflows extract translatable content from a file and hand it to a linguist. Whether alt text comes along depends entirely on the tooling and how it was configured. In HTML, an alt attribute is often extracted; in a PDF, a /Alt entry in the tag tree usually is not. In Word, the description sits in an image’s properties dialogue, which many extraction paths never open.

So the linguist never sees it. Nobody withheld it — it simply was not in what they were given. And because alt text is invisible on screen, no reviewer notices at proofing, and no visual QA catches it.

The same blind spot covers a few other metadata fields that matter:

• Table summaries and captions, where they exist as properties rather than visible text
• Form field labels and tooltips in fillable PDFs
• The document title in file properties, which screen readers often announce before anything else
• Link purpose text, where a link’s accessible name differs from its visible text
• Long descriptions attached to complex images like charts and maps

A document can be perfectly translated in its body and entirely English in all of these.

Which requirement does this break?

Alt text itself is WCAG 1.1.1 Non-text Content (Level A) — the requirement that non-text content has a text alternative serving an equivalent purpose.

The word doing the work is equivalent. An English description in a Spanish document is not an equivalent alternative for the person the Spanish document was produced for. It fails the criterion on purpose rather than on presence, which is exactly the sort of failure automated checkers cannot detect: a scanner sees alt text is present and reports a pass.

There is a related failure worth noting. Under 3.1.2 Language of Parts (Level AA), a passage in a different language should be marked as such. So English alt text left inside a Spanish document should — strictly — be marked English so it is at least pronounced correctly. That is not a fix. It is a way of making the failure audible rather than garbled, and the real answer is to translate it.

WCAG 2.1 Level AA is the standard behind the ADA Title II rule, the HHS Section 504 rule, and Section 508 procurement; the ADA Title II deadline post has which applies to whom and by when.

How do I check my own files?

In a PDF, open the tag tree in Acrobat and inspect a figure’s alternate text. Or run the built-in accessibility check, which will tell you whether alt text exists — then read it yourself to see what language it is in. The tool confirms presence; only you can confirm language.

In Word, right-click an image and open the alt text pane. Fast, and usually conclusive across a document set produced from one template.

In HTML, view source and read the alt attributes on a translated page.

The definitive test is a screen reader with a voice in the target language. Navigate to an image and listen. If the description arrives in English, you have found it.

Our PDF accessibility checker will report on a specific file’s structure, including whether alternative text is present.

What good translated alt text looks like

Not a word-for-word translation of the English, necessarily. Alt text describes purpose in context, and context can differ:

• Describe function, not appearance, where the image does something. A button image is described by what it does.
• Keep it as long as it needs to be and no longer. A decorative flourish should be marked decorative and given no description at all — in any language.
• Translate the content of the image too. A diagram containing English labels needs a description in Spanish that conveys the Spanish meaning of those labels, not a Spanish sentence pointing at English words.
• Charts and maps need real descriptions. “Chart showing revenue” is useless in every language. What the chart shows is the alternative.
• Numbers, units and dates follow target-language conventions. A description containing a date should use the target locale’s format.

This last set is the reason translated alt text is genuinely a translation task with an accessibility brief, rather than a string-replacement job.

How to stop it happening again

1. Include alt text in the scope you send for translation. Explicitly. Ask your vendor whether their extraction includes it — most will say no once asked directly.
2. Write alt text in the source before translating. If the English document has no alt text, translation cannot produce any. Fixing the source template fixes every language downstream.
3. Add it to your QA checklist as a named item, because it will never be caught by reading the document.
4. Test with a screen reader in each language you publish, on at least one representative document per template.
5. Put it in the contract if a vendor is producing the deliverables. How to write accessibility into an RFP has clause language that covers translated deliverables specifically.

Where Taika fits

We treat alt text as content, because it is. When we remediate and translate a document in one pass, the image descriptions are written in the target language by someone who read the document — and verified with a screen reader in that language.

That is the difference between doing both trades and doing one: an accessibility vendor cannot write Spanish alt text, and a translation vendor is usually never shown it.

Start at document accessibility, or accessibility and compliance services for a full multilingual estate. The companion pieces are translated documents and WCAG language of parts and Arabic and RTL PDF accessibility.

Have a translated document set you have never screen-reader tested? Request a quote with the languages and a rough document count. We will tell you what we find — and in our experience, alt text is the first thing.