Protect PDF
PDF → PDF (encrypted)Add an open password and decide what readers may print or copy.
1 · PDF
2 · New password
What readers may still do
Permissions are a request to the reader software, not a lock. Anyone who can open the file can work around them; the password is the part that actually protects it.
3 · Result
About Protect PDF
Payroll, contracts, medical results, board papers — documents that travel by email and should not open for whoever finds the attachment. This adds an open password using AES encryption, and lets you decide what a reader who does have the password may still print or copy.
How it works
- 1Pick the PDF you want to lock.
- 2Type the password twice, and choose what readers are still allowed to do.
- 3Press Protect PDF and download the encrypted file.
Questions
- Is the password sent anywhere?
- No. Encryption happens in this browser tab: the password is used to derive a key locally and is discarded when you close the page. It is never transmitted, logged or stored, which also means we cannot help you recover it.
- What happens if I forget the password?
- The document is unrecoverable. That is the point of encryption, and it applies to us as much as to anyone else. Write the password down somewhere safe before you send the file.
- How strong is the encryption?
- The file is encrypted with AES, the standard modern PDF readers expect, so it opens normally in Acrobat, Preview, Chrome and Edge once the password is given. The real strength is your password: a short or common one can be attacked by guessing, whatever the cipher.
- Do the printing and copying permissions actually stop anyone?
- Not reliably. Permissions are instructions to reader software, and any reader can choose to ignore them — anyone able to open the document can work around them. Treat them as a signal of intent. The password is the part that provides real protection.
- Can I protect a PDF that already has a password?
- Yes. Enter the existing password when the tool asks for it, then set the new one. This is how you change a password: unlock with the old, protect with the new.
Next you might need
This page does the work itself, in this tab. Nothing about your file — not its name, not its contents — is sent to a server. Close the tab and no copy remains.