Password protect a PDF

Add a password so the file can't be opened without it.

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Password protection is the right control for a document you are about to email or hand over on a drive. Doclium encrypts the file with AES-256, so it cannot be opened without the password.

🔒 Never used for AI training: delete a document and it is gone from the server.
⚡ No watermarks: on any tool, including the free tier.
↩ Undo: step back through your last 10 edits.

How to password protect a PDF

  1. 1Upload the PDF you want to protect.
  2. 2Choose a password.
  3. 3Download the encrypted file.

Questions people ask

What happens if I lose the password?

The file cannot be opened. Doclium does not store your password and cannot recover it, which is what makes the encryption meaningful.

What encryption is used?

AES-256, the standard supported by current PDF readers.

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