Protect PDF

Encrypt your PDF files with a secure password to prevent unauthorized access online instantly.

Drop a PDF here

or click to browse

All processing happens locally on your device — your files are never uploaded to any server.

How to Password Protect a PDF

Lock down your sensitive PDFs with military-grade AES encryption.

1. Upload File

Select the PDF document you want to secure with a password.

2. Set Password

Type a strong, memorable password. Make sure not to lose it!

3. Encrypt & Save

Click protect. We will encrypt the file locally and download the secured version.

Frequently Asked Questions

The most dangerous thing you can do is upload an unencrypted private document to a cloud server to encrypt it. RunOnLocal does it right on your machine.

Is my data private and secure?

Yes, absolutely 100%. By utilizing modern local browser technologies, we process your files directly on your computer or phone. No servers, no uploads, no compromises.

How fast is the processing?

Because there are no uploads or downloads to a remote server, processing is virtually instant. Even large PDF files are processed in milliseconds without eating up your network bandwidth.

What encryption do you use?

We use the industry-standard 256-bit AES encryption. It is virtually unbreakable and used by banks and governments globally.

Are there any limits or watermarks?

Enjoy completely unrestricted access to the tool! You can use it an unlimited number of times for free. We never artificially cap your file sizes, demand subscriptions, or ruin your final documents with unwanted branding or watermarks.