Protect PDF
Add a password to a PDF with strong AES-256 encryption so only people with the password can open it. Free and processed entirely in your browser.
Drop a file here or click to browse
PDF · processed locally, never uploaded
100% in-browser — your files are never uploaded to a server.
Protect PDF locks your document with a password using strong AES-256 encryption. Anyone who wants to open the PDF will need the password you set — ideal for sharing contracts, statements or any sensitive file safely. The encryption happens entirely in your browser.
How to use Protect PDF
- 1Upload the PDF you want to protect.
- 2Choose a password.
- 3Click “Protect PDF”.
- 4Download the password-protected PDF.
Frequently asked questions
What encryption is used?
Files are encrypted with AES-256, the same strong standard used for secure documents — applied locally in your browser by a WebAssembly engine.
What happens if I forget the password?
There is no way to recover it. The password isn't stored anywhere, so keep it somewhere safe before sharing the file.
Can the recipient open it without the password?
No. The password is required to open the PDF in any reader.
Are my files uploaded to a server?
No. Every PDF tool here runs entirely in your browser using your device's own processing power. Your files never leave your computer, which makes it private and fast.
Is this tool really free?
Yes — it is completely free with no sign-up, watermarks or daily limits. You can process as many files as you like.
This tool processes your files locally in your browser and does not upload them anywhere. Always keep a copy of your original file.
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