Sada Files
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Upload PDFs

Add PDFs from your device to get started

Drop your PDF files here

Drag & drop, paste, or click to select PDF files for Protect PDF.

Or drag and drop up to 500 files here

PDF

Protect PDF online, free

Encrypt a PDF with an open password and an owner password — AES-128 or AES-256 — and set print, copy, edit and annotate permissions.

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

How to use Protect PDF

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    Add your PDF files

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

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    Fine-tune the settings

    Set algorithm in the Fine-tune panel, or keep the defaults — they suit most files.

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    Run Protect 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 Protect PDF can do

  • Algorithm: aes256 and aes128
  • Private by design — files are processed in your browser and never uploaded
  • Batch processing — up to 500 files at once
  • Free with no sign-up, no watermark and no daily limit

Protect PDF — frequently asked questions

Is Protect PDF really free?

Yes. Protect 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. Protect 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 Protect PDF accept?

Protect 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. Batch as many files as you like.

Can I chain Protect 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 Protect 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 Protect PDF fully offline.

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