Protect PDF
Set a password and download an encrypted copy. The file and the password are processed on your device — we never see either.
Choose a PDF to protect
or drop files here
▚ files open locally — nothing is uploaded
- 01Open the PDF — it stays local.
- 02Set a password (at least 4 characters) and repeat it to confirm.
- 03Click Encrypt. The protected copy downloads; readers will demand the password to open it.
You password-protect a PDF at the exact moment you've concluded its contents are sensitive: a payslip going by email, a contract on a shared drive, medical results for one person's eyes. Handing that file — plus the password — to an upload-based website first is the one move that makes no sense.
ZorPDF encrypts in place. Your browser performs the encryption, the password lives in the tab's memory for the seconds the work takes, and what leaves your device is only what you choose to send: a file that's already locked.
What does the password actually do?+
The file is encrypted (AES) so that PDF readers — Adobe, browsers, phones — demand the password before showing any content. Without it, the file's contents are ciphertext, not just hidden.
Where is my password processed?+
In your browser's memory, on your device, during encryption — and nowhere else. It isn't transmitted, logged or stored. That also means we cannot recover it: if you forget the password, the file stays locked.
Why does encrypting on-device matter so much?+
Think about what an upload-based protect tool sees: your unprotected document AND your chosen password, together. You're trusting them at the exact moment you've decided the file needs protecting. Local encryption removes that contradiction entirely.
Can I remove the password later?+
Yes — as long as you know it, the Unlock PDF tool strips the encryption and saves an open copy, also locally.