Protect PDF

Add a password to a PDF without uploading. Encrypt with AES-256 so opening the file requires a password — privately in your browser.

Password-protect a PDF in your browser

Add a password so recipients must unlock the file to open it. Encryption stays on your device — nothing is uploaded.

What you can do with it

Share sensitive contracts
Send a password-protected PDF and share the password through a separate channel.
Limit copying and editing
Use advanced permissions to restrict printing, copying, or modifying.

How to password-protect a PDF

  1. Open your PDF — it loads locally with no upload.
  2. Enter and confirm a password (optional: owner password and permissions).
  3. Download the protected PDF.

Password-protect a PDF on your device

Encryption runs in the browser so the plaintext file is never uploaded to set a password. Share the password out-of-band (call, Signal, separate email). Optional permission flags can limit printing or copying depending on the reader.

Protect vs unlock vs redact

Protect locks the file. Unlock removes a password you already know. Redact permanently obscures content even for people who can open the file. Use redact when recipients should not see certain fields even after unlocking.

Related reading and tools

  • Unlock PDFRemove a password you own before further editing.
  • Redact PDFHide content that should never be readable.
  • Remove metadataStrip identifying properties before locking and sending.

Frequently asked questions

Is my PDF uploaded?
No. Encryption runs entirely in your browser. Your file and password never leave your device.
What encryption is used?
AES-256 (PDF 2.0), compatible with modern PDF readers.
Can I set an owner password separately?
Yes. Use advanced options for an optional owner password and printing/copying/modifying permissions.
Does this modify my original file?
No. A new protected PDF is created when you download. Your original stays unchanged on disk.

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