FREE · PDF TOOLS
Protect PDF with Password.
Encrypt a PDF with AES-256 and an opening password.
How to use Protect PDF with Password
Choose the PDF, enter settings, generate and inspect the downloaded copy. Your original file is unchanged.
How it works
Encrypt a PDF with AES-256 and an opening password. Use 8–200 printable ASCII characters. A random owner password is generated locally. This is encryption, not a cryptographic document signature. Files are processed on your device; no PDF upload is required.
Example
Choose a local PDF and adjust the displayed settings.
Questions about Protect PDF with Password
Is Protect PDF with Password free, and do I need an account?
Yes. This tool is free to use in your browser without an account. Processing takes place on your device.
What are the limits and what should I check?
20 MiB combined input; 200 pages for structural operations, 60 seconds for QPDF operations. Use 8–200 printable ASCII characters. A random owner password is generated locally. This is encryption, not a cryptographic document signature. Review the downloaded document, especially page order and watermarks.
Is my input sent to a server?
Your input is processed in your browser and is not uploaded by this tool. Files and pasted text are cleared when the page is refreshed. Normal website requests are still required to load the page and its libraries. Read the privacy explanation.