Password Protect a PDF
Protect PDF encrypts a document with a password using AES-256 encryption. The encryption runs in your browser, so the file and password are never uploaded.
Drag & drop your PDF here
or
No signup needed · Encrypted locally in your browser — never uploaded
- Free
- No signup
- No watermark
- Files stay on your device
What is Protect PDF?
A password stops anyone without it from opening your PDF. This tool encrypts your file with AES-256, the same strength used by banks and government systems, and saves a protected copy.
The encryption runs in your browser using a WebAssembly build of the open-source qpdf library. Neither your file nor your password is uploaded or stored by this site.
How to protect pdf in 3 steps
Add your PDF
Drag it in or choose it from your device.
Choose a password
Type the password that will be needed to open the file.
Download
Your AES-256 protected PDF downloads.
Good to know: One password is applied. Permission restrictions (printing, copying) are not set separately.
When to use it
Use it for payslips, contracts, medical letters or anything you email. Share the password through a different channel than the file, for example by phone or message.
Tip: keep the original unprotected copy in a safe place. A forgotten password cannot be recovered.
Related PDF tools
Finish the job with another free tool.
Protect PDF – frequently asked questions
Can you recover my password if I forget it?
No. The password is never stored, and strong encryption cannot be reversed without it. Keep a copy of the password.
Is my file uploaded to encrypt it?
No. Encryption runs on your device in a WebAssembly module loaded from this site.
Which encryption is used?
AES-256. The same password is used to open the document and as the owner password.
Is my file uploaded to a server?
No. Protect PDF runs in your browser, so the file stays on your device. Pagemint has no accounts and does not store your documents.
Is Protect PDF free?
Yes. Protect PDF is free to use, with no signup, no watermark and no daily limit.