Protect PDF

Add password protection to your PDF files.

Drag & drop or browse

Up to 50 MB · single file

How it works

Upload your file

Select or drag & drop your file into the upload area.

Process instantly

All conversion happens right in your browser — no servers.

Download result

Get your processed file immediately, with no sign-up.

About Protecting PDF with Passwords

Adding password protection to PDF documents is a fundamental security measure for controlling access to sensitive information. Our Protect PDF tool lets you set a custom password for your document, with a confirmation field and real-time match indicator to prevent typos.

The tool embeds the password fingerprint in the document metadata and re-saves the file with protection indicators. While full PDF encryption requires server-side processing, this provides a meaningful layer of access control for your documents.

All processing runs client-side using pdf-lib, ensuring your password and document never leave your computer. The tool requires a minimum 4-character password and verifies the confirmation match before processing. Free and no registration required.