Password-protect a PDF with AES-256 encryption, entirely in your browser. Preview the source and locked result, then download a PDF that requires your password to open.
No PDF selected.
One unencrypted PDF · up to 50 MiB and 500 pages
Keep your password somewhere safe. TheBrowserBox does not save it and cannot recover it. Anyone who knows the password can open and copy the document.
Ready. Choose a PDF.
Finish editing before locking. Existing encrypted PDFs, interactive forms and signature fields are unsupported. Encryption rewrites the file; digital signatures are not preserved. Pages stay as PDF content rather than images.
Check your pages before and after encryption. The generated preview uses your password only in this tab. The downloaded PDF still requires the password in a compatible PDF reader.
Choose a file to see its pages. Previews are rendered locally.
No document selected.
Ready for a document.
Working previews show planned page operations. Generated-result mode renders the actual exported PDF, image, or selected ZIP part. Preview resolution is reduced for speed; download quality is unchanged. Links, scripts and attachments are not opened.
Your PDF and password are never uploaded to a server. A self-hosted QPDF WebAssembly engine runs in a cancellable browser worker. No accounts, saved passwords or remote processing are used.
Yes. QPDF applies AES-256 PDF encryption and a nonempty opening password. It is not merely a viewer restriction. The PDF requires that password in compatible readers. Anyone who knows the password can read or copy its contents.
The preview opens the generated PDF locally using the password you entered. The downloaded file is encrypted and still requires the password. Changing either password field discards the previous output.
No. Passwords are not saved or sent to a server. Clear the tool or close the tab to release the working files and password fields. Store your password securely before sharing the PDF.
One unencrypted PDF up to 50 MiB and 500 pages. Interactive forms and signature fields are unsupported. Encryption rewrites the PDF, so digital signatures are not preserved. Output is limited to 100 MiB and processing to 60 seconds. Use a modern browser with WebAssembly support.
Page content, sizes and rotations are retained without rasterizing. This tool requires a password to open the file; it does not promise to prevent copying or editing after opening. Finish other PDF edits before locking.
