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Protect PDF

Add a password to your PDF without ever uploading it. Uses strong client-side encryption. Your password is never transmitted.

About Protect PDF

Protect PDF adds a password to your document using strong AES encryption applied entirely in your browser. The password is never sent over the network — it's used locally to encrypt the PDF, and the encrypted file is what you download.

Use it before emailing tax forms, contracts, financial statements, or any document you'd rather not have readable in someone else's inbox.

Compare this to Adobe's online protector or iLovePDF: both upload your file to their servers along with the password. PDFVibe doesn't.

How to protect pdf in your browser

  1. 01
    Open the protector

    Visit pdfvibe.app/tools/protect.

  2. 02
    Drop your PDF

    Drag the file in.

  3. 03
    Enter a password

    Choose a strong password. PDFVibe encrypts the document with it locally.

  4. 04
    Confirm

    Re-enter the password to avoid typos.

  5. 05
    Download

    Save the encrypted PDF. The original is untouched.

Frequently asked questions

What encryption is used?

AES, applied via the qpdf-wasm engine running in your browser.

Is the password uploaded?

Never. It stays in your browser and is used to derive the encryption key locally.

What if I forget the password?

We can't recover it — there's no copy of it anywhere. Use a password manager.

Does it work for sensitive docs?

Yes. Tax forms, contracts, medical reports — anything you'd email — benefits from a password.

Adobe alternative?

Yes. Same outcome (password-locked PDF), but no upload and no Adobe account required.

Why client-side?

Most online PDF tools — Adobe Acrobat Online, iLovePDF, Smallpdf — upload your file to their servers, run the operation, then send the result back. PDFVibe runs the same operation in your browser using WebAssembly and pdf-lib. The file never travels anywhere. Open your browser’s Network tab while using Protect PDF and you’ll see no outbound file transfers.

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