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Protect PDF

Add password protection to your PDF. Processed 100% in your browser — your file is never uploaded.

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Drag & drop a PDF file here
or
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Uses RC4-128 encryption (standard PDF security). Processed entirely in your browser.

Encrypting...
✅ PDF Protected Successfully!
Features
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100% Private

All encryption happens in your browser. Your file and password never leave your device.
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Real Encryption

Uses RC4-128 bit standard PDF encryption — recognized by Adobe Acrobat and all major PDF readers.
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Instant

No upload time. Encryption happens on your device in seconds.
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Free Forever

No sign-up, no limits, no watermarks added.

Frequently Asked Questions

What type of encryption is used?

We use RC4 128-bit encryption as defined in the PDF specification (Standard Security Handler, Revision 3). This is supported by all major PDF readers including Adobe Acrobat, Preview, and Foxit.

Can I open the protected PDF on iPhone or Android?

Yes. The RC4-128 Standard Security Handler is a widely supported PDF standard. Apple Files app (iOS 16+), Samsung PDF Viewer, Adobe Acrobat Mobile, and most other mobile PDF readers will recognize the password protection and prompt you to enter your password before opening.

Is my file or password sent to a server?

No. The encryption happens entirely within your web browser using JavaScript. Your PDF and your password never leave your device. We have no access to them.

What happens if I forget the password?

There is no way to recover a forgotten password from the encrypted file. Please keep your password safe — we do not store it anywhere.