Protect PDF
Drag and drop, or click to upload a PDF
Drop in a PDF, choose a password, and download a copy that requires it to open - no Adobe Acrobat or other software required. Encryption runs on mupdf compiled to WebAssembly, entirely inside this browser tab; the file and password are never uploaded to a server.
How to use it
- Drag and drop, or click to upload, your PDF.
- Enter the password you want to protect it with.
- Click "Protect PDF" to encrypt it.
- Download the protected PDF - the file and password never leave your browser.
Frequently asked questions
Is my PDF or password uploaded anywhere?
No - encryption happens entirely in your browser using mupdf (a WebAssembly PDF engine). Nothing is sent to a server.
What encryption does this use?
AES-256, the modern standard for PDF password protection.
What if my PDF already has a password?
This tool is for adding protection to a PDF that doesn't already have one. Remove the existing password first if you need to replace it.
What happens if I forget the password?
There's no recovery - write it down somewhere safe. Forgetting it means losing access to the protected PDF, the same as with any encrypted file.
Can I restrict printing or copying separately from the open password?
Not yet - this sets a single password required to open the file, without separate permission restrictions.
What's the protected file called?
Your original filename with -protected added, like report-protected.pdf.