Adobe InDesign plugin · PDF/UA-1 · WCAG
Accessible PDFs, without the guesswork.
TagAlly Pro turns accessibility from a mystery into a checklist. It inspects your InDesign document, fixes what it can, repairs the PDF after export, validates against PDF/UA-1 — and hands you the report that proves it.
Runs entirely on your own machine. No document ever leaves your computer.
Exporting a “tagged PDF” is not the same as an accessible PDF
InDesign gets you part of the way. The rest is invisible work that only shows up when a validator — or a real reader with a screen reader — hits the document.
Silent gaps in the export
InDesign leaves out things the standard requires: the PDF/UA identifier, the “display document title” flag, descriptions on links, and the correct root language. None of them are visible in the layout.
Structure that reads wrong
Without a defined reading order, the stacking order of your frames decides what a screen reader reads first. That is almost never the order a human would read.
Findings you cannot interpret
A validator reports “7.4.2 heading level skipped” or “content not tagged”. Useful for an expert, useless when you just want to know which frame on which page to fix.
How TagAlly Pro works
One guided pass through your document, then export and proof. Every finding points at the object it came from, and most of them have a button that fixes it.
Check
Six steps with traffic-light status: metadata and language, tag mappings, headings, artifacts, alt texts and tables and contrast, reading order. A progress bar shows how far along the document is.
Fix
Findings carry their own repair: assign a tag to a paragraph style, mark decoration as an artifact, set a header row, write an alt text. “Show” selects the object in the layout so you always see what you are changing.
Export & repair
Export as a tagged, interactive PDF. TagAlly then post-processes a copy automatically — identifier, title display, language, link descriptions, tag corrections and font fixes.
Validate & prove
The repaired PDF is validated against PDF/UA-1 with veraPDF. You get a printable report: the machine result plus the manual checklist that no software can judge for you.
What makes it different
Visual overlays
See accessibility in the layout instead of in a list. One overlay marks every image green, blue or red by alt-text status and flags tables without a header row. Another numbers every object in reading order.
Record the reading order
Click the objects in the order they should be read — TagAlly builds the article as you go and numbers each click on screen. Work across several sessions and several articles; nothing you already recorded is lost.
Built-in contrast check
Text colour measured against its real background to WCAG thresholds, right inside the document — no external eyedropper tool. Text sitting on photos is listed separately for a visual check, and you can sign those off.
Structure view
See the finished tag tree the way a screen reader walks it: reading order, heading hierarchy, images with their alt texts, tables and language switches — generated from the validated PDF, no extra software.
Optional AI alt texts
Let a vision model draft alt texts for images that have none. Suggestions appear editable in the panel and are only written when you accept them. Bring your own API key, or run a local model — the feature is entirely optional.
The report is the deliverable
A designed, printable conformance report in eleven languages: machine result, violation table, and a manual checklist referencing the Matterhorn Protocol — with space for remarks and a signature.
Your documents stay on your machine
TagAlly Pro consists of the InDesign panel and a small helper program that runs locally on your own computer and listens only on 127.0.0.1. Checking, post-processing and validation all happen there. Nothing is uploaded, and there is no account to create.
- No document, page or image is sent anywhere during checking, export, repair or validation.
- No telemetry, no usage tracking, no analytics inside the plugin.
- The one exception is opt-in and clearly marked: if you enable AI alt texts with your own provider key, the individual image is sent to that provider to generate a suggestion. Leave it off and nothing leaves your machine.
Why this matters now
Since 28 June 2025 the European Accessibility Act — implemented in Germany as the Barrierefreiheitsstärkungsgesetz — extends accessibility obligations to a wide range of private-sector products and services, not just public bodies. Public sector bodies have been covered for years under EN 301 549 and national law.
For documents, the relevant technical standard is PDF/UA-1 (ISO 14289-1). The Matterhorn Protocol breaks that standard into checkable conditions — some machine-testable, some requiring human judgement. TagAlly Pro follows exactly that split: it automates what can be automated and gives you a structured checklist for the rest.
Worth knowing: no tool can certify accessibility on its own. Whether an alt text actually describes the image, or whether the reading order matches the intended meaning, is a human judgement. Any vendor who promises full automation is overselling. TagAlly makes the human part short, guided and documented.
Requirements
| Adobe InDesign | Version 2025 (20.0) or newer, on macOS or Windows |
|---|---|
| Helper program | Included; runs locally and needs a Java runtime for the PDF repair step |
| Validator | veraPDF (free, open source) — used for the PDF/UA-1 validation |
| Interface languages | English, German, French, Spanish, Italian, Dutch, Portuguese (BR), Polish, Danish, Swedish, Norwegian Bokmål |
| Internet | Not required. Only the optional AI alt-text feature contacts a provider you choose. |
The report language is set separately from the panel language — so you can work in your own language and still hand a client or authority a report in theirs.
Get TagAlly Pro
TagAlly Pro costs 199 euros per year and per seat, and is sold through the Adobe Creative Cloud Marketplace. Buying and invoicing run through Adobe; the licence and the support come from us.
Or read the FAQ first — it answers most questions in detail.