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Module · PDF

PDF Protect

Add a password to any PDF. Real 128-bit RC4 encryption — enforced by every major PDF reader. Runs 100% in your browser.

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Guide

How PDF Protect works

Step 01
Drop your PDF

Choose any .pdf file. Nothing is uploaded — encryption runs locally.

Step 02
Choose a password

Pick a strong password (4+ chars). Confirm it. Anyone opening the PDF will be prompted for this password.

Step 03
Download protected PDF

Real 128-bit RC4 encryption — enforced by Adobe Acrobat, Preview, Chrome, Firefox and every other PDF reader.

FAQ

Frequently asked

How strong is the encryption?+

128-bit RC4, the PDF 1.4 standard. It's the same encryption used by Acrobat's default "Password Security" preset for compatibility with all readers.

Can you recover a lost password?+

No — there's no back-door. Store your password in a password manager.

Does it work on my phone's PDF reader?+

Yes. Every major PDF reader on desktop, iOS and Android supports 128-bit RC4 encryption.

Is the PDF uploaded?+

Never. Encryption runs entirely in your browser using the pdf-encrypt-lite library (~9 KB gzipped).

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