How to password-protect a PDF
- Drop your PDF above.
- Set a password. Type it twice to confirm. Optionally restrict printing, copying, or editing under the advanced options.
- Click Protect PDF, then Download. The encrypted copy is built on your device; anyone opening it will need the password.
Encryption that happens on your device
Most “protect PDF” sites upload your document, encrypt it on a server, and email or download it back — which means your confidential file, and sometimes your password, pass through someone else's computer. Sleek PDF encrypts the PDF right in your browser using standard PDF encryption, so the file and the password never leave your device. It's the right way to protect a contract, a bank statement, or medical records before sending them.
Common uses for password-protecting PDFs
- Secure a bank statement — add a password before emailing financial documents.
- Protect medical records — encrypt health documents so only the recipient can open them.
- Restrict printing or copying — stop recipients from printing or copying a shared file.
Frequently asked questions
How do I password-protect a PDF?
Drop your PDF above, type a password (twice), and click Protect PDF. The encrypted copy downloads immediately and will ask for that password every time someone opens it.
What kind of encryption is used?
Standard PDF encryption — the same password-to-open scheme every PDF reader understands. The file is encrypted in your browser and the password is never sent anywhere.
Can I stop people from printing or copying?
Yes — under “Restrict what viewers can do (advanced)” you can disallow printing, copying, or editing. Those limits apply to people who open with the regular password; set a separate owner password to keep full rights for yourself. Note that permission limits are respected by well-behaved viewers but aren't a hard guarantee, whereas the open password genuinely encrypts the file.
If I lose the password, can I get in?
No. There's no backdoor — that's the point of encryption. Keep the password somewhere safe.
Is my PDF or password uploaded?
No. Encryption runs entirely in your browser; neither the file nor the password ever leaves your device. You can confirm it in your browser's network tab.