What encryption does this tool use?

It applies 256-bit AES encryption, an industry-standard level of protection widely used for sensitive documents.

Will the password protect the file everywhere it is sent?

Yes — the password requirement is embedded in the file itself, so it applies no matter where the file is opened or how it was delivered.

What happens if I forget the password?

The document cannot be opened by anyone, including us — we do not store passwords, so there is no recovery option. Keep your password somewhere safe.

Do I need to install anything on Windows to use this?

No — it works in any modern Windows browser (Edge, Chrome, Firefox) with nothing to download or install.

Will this work on both Windows 10 and Windows 11?

Yes — since it runs entirely in your browser, it works identically on Windows 10, Windows 11, or older supported versions.

Security

Protect PDF on Windows

Windows doesn't include a built-in way to do this beyond what a basic PDF reader offers, so most people either hunt for a downloadable utility or turn to a browser-based tool instead. My PDF works in any browser on Windows — Edge, Chrome or Firefox — without installing anything or restarting your computer.

Use the Protect PDF Tool

No registration required
Files deleted automatically
Works in any browser

Why This Matters

What Is a PDF Password Protection Tool?

A PDF password protection tool encrypts a document so that it can only be opened by someone who knows the password you set, using industry-standard 256-bit encryption. Once protected, the file itself — not just a viewer's settings — enforces the password requirement, so it stays protected no matter where the file is copied, emailed or stored.

Step by Step

How to Protect PDF on Windows

Upload Your PDF

Drag in the PDF you want to protect, or click to browse and select it. On Windows, just drag the file straight from File Explorer into the upload area.

Choose a Password

Enter and confirm a password of at least 4 characters — choose something memorable but not easily guessed.

Click Protect PDF

Our server encrypts the document with 256-bit encryption, typically within seconds.

Download the Protected File

Save your encrypted PDF, then share the password with your recipient through a separate channel.

Recommended Tool: Protect PDF

Add a password to keep sensitive files private.

Open Protect PDF

Get Better Results

Tips

Share the Password Separately — Send the protected PDF and its password through two different channels — for example, email the file and text the password.
Choose a Password You Will Remember — A password that only you can recall is safer, but a lost password means the document is permanently inaccessible — write it down somewhere secure.
Windows Defender or antivirus software occasionally flags downloaded PDF utilities as unfamiliar — a browser-based tool sidesteps that entirely since nothing is installed.
If you're on a work or school Windows PC, IT policy often blocks installing new software; a browser tool works even under locked-down permissions.

Avoid These

Common Mistakes

Uploading a file that is already password-protected without unlocking it first — most operations require an unencrypted starting file.
Assuming a converted or compressed file replaces the need for the original — keep your source file until you have confirmed the result looks right.
Not checking the 50 MB upload size limit before starting, then wondering why a very large scan fails to upload.
Downloading a third-party Windows utility from an unfamiliar site instead of using a browser — a common source of bundled adware.