Sada Files
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Upload PDF

Add PDF from your device to get started

Drop your PDF here

Drag & drop, paste, or click to select PDF for Auto-tag PDF.

Or drag and drop a file here

PDF

Auto-tag PDF online, free

Generate structure tags — headings, lists, tables, reading order — for an untagged PDF.

  • Runs in your browser — no upload
  • Free, no sign-up, no watermark
  • PDF

How to use Auto-tag PDF

  1. 1

    Add your PDF file

    Drop a file on the page, paste it, or click Select Files. Nothing is uploaded — it opens straight in your browser.

  2. 2

    Fine-tune the settings

    Set language and image alt text in the Fine-tune panel, or keep the defaults — they suit most files.

  3. 3

    Run Auto-tag PDF

    Press the start button. Processing happens on your device, usually in seconds.

  4. 4

    Download the result

    Save the finished file, or continue with another tool without downloading in between.

What Auto-tag PDF can do

  • Language — BCP 47 code, e.g. en, hi, ta
  • Image alt text — Used for figures without alt text
  • Private by design — files are processed in your browser and never uploaded
  • Free with no sign-up, no watermark and no daily limit

Auto-tag PDF — frequently asked questions

Is Auto-tag PDF really free?

Yes. Auto-tag PDF is free forever on Sada Files — no ads, no premium tier, no watermark, no daily cap that pushes you to pay. Every option on this page is available to everyone.

Do I need to sign up or create an account?

No. There is no account system at Sada Files. Open the page, drop your file, pick your options and save the result. History and saved workflows stay on your device.

Is my file uploaded anywhere?

No. Auto-tag PDF runs on your device — in your browser using WebAssembly, or inside the free native app. Your file never leaves your computer or phone, which is why there is no upload wait.

Which formats does Auto-tag PDF accept?

Auto-tag PDF accepts PDF. Files are identified by their content, not their extension, so a mislabelled file still works.

Is there a file size or file count limit?

Only what your device can handle. Because processing happens locally there is no server cap, no queue and no "upgrade for larger files" message.

Can I chain Auto-tag PDF with other tools?

Yes. After every result a Continue with… menu lists every tool that accepts this output, and the file is handed over in memory. Save the chain as a workflow and re-run it on hundreds of files, or call it in one API request.

Does Auto-tag PDF work on my phone?

Yes. The web app works on Android and iOS browsers, and the free Sada Files app for Android, iOS, Windows, Linux and macOS runs Auto-tag PDF fully offline.

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