Get started
All Tools Merge PDF Split PDF Compress PDF PDF to JPG JPG to PDF PDF to PNG PNG to PDF PDF to Word Word to PDF PDF to Excel Excel to PDF PDF to PowerPoint PowerPoint to PDF Rotate PDF Delete PDF Pages Extract PDF Pages Reorder PDF Pages Watermark PDF Add Page Numbers Sign PDF Crop PDF PDF Metadata Editor Protect PDF Unlock PDF Pricing FAQ About Contact

Protect a PDF with a password

Encrypt a PDF so it can only be opened with a password.

Protect PDF needs a connected conversion service. This operation can't be done reliably in the browser or with plain PHP, so Quire is built to call a real document-conversion engine here. Once CONVERT_API_KEY is set in config/config.php, this tool becomes fully functional — nothing is faked in the meantime.

Drag & drop a file here, or click to browse

Accepts .pdf · processed via connected service
🔒 When connected, files are sent to the configured conversion service over an encrypted connection and are not stored longer than needed to process your request.

How it works

1

Upload your PDF.

2

Set an open password.

3

Download the encrypted file.

Frequently asked questions

Real PDF encryption needs a cryptography library beyond what plain browser JavaScript can safely provide — Quire connects to a server-side engine for this rather than faking it.

Related tools

Unlock PDF Sign PDF PDF Metadata Editor