Protect PDF with a password
Encrypt your PDF with strong AES-256 protection. Set a password to open the file and optionally control printing, copying and editing — directly in your browser.
Password protect a PDF without uploading it
Add real PDF password encryption directly in your browser. Your PDF and password stay on your device while the protected copy is generated.
Encryption runs locally in your browser using a WebAssembly build of QPDF. Keep your password safe — this tool cannot recover a forgotten password.
Encrypt PDFs with AES-256 and a password required to open the document. Your file and password stay in your browser during processing.
Why use this Protect PDF tool?
AES-256 PDF encryption
The tool uses QPDF WebAssembly to create a password-protected PDF using 256-bit AES encryption.
Runs in your browser
Your PDF and password are processed locally rather than uploaded to a server for encryption.
Control permissions
Choose whether compatible PDF readers should allow printing, copying or document modifications.
Original stays unchanged
The original PDF is never overwritten. The tool creates a separate encrypted copy for download.
How to password protect a PDF
Protect your document in four simple steps.
Choose your PDF
Upload the PDF you want to protect or drag it into the tool.
Set a password
Enter a strong password and confirm it. Store the password safely before downloading.
Set permissions
Choose whether compatible readers should allow printing, copying or editing.
Download
Click Protect PDF and download the new encrypted PDF.
Protect PDF FAQs
Yes. This free Protect PDF tool encrypts a PDF with AES-256 and lets you set a password required to open the protected file.
No. The PDF and password are processed locally in your browser using a WebAssembly PDF encryption engine. The file is not uploaded to our server for protection.
The tool uses QPDF compiled to WebAssembly and creates a 256-bit AES encrypted PDF. Current QPDF documentation describes 256-bit encryption as the modern AES-based PDF encryption format.
There is no password recovery built into this tool. Keep the password in a secure password manager or another safe location before protecting the PDF.
Yes. You can request restrictions on printing, text and graphic extraction, and document modification. PDF permission restrictions are enforced by compatible PDF readers and should not be treated as an absolute DRM mechanism.
No. The original PDF remains on your device unchanged. The tool creates a separate protected PDF for download.