Protect PDF
Encrypt a PDF with a password using AES so only people with the password can open it. Encryption happens in your browser — your file and password are never uploaded.
Select a PDF to password-protect
Processed locally in your browser — never uploaded.
Encrypt a PDF with a password using AES so only people with the password can open it. Encryption happens in your browser — your file and password are never uploaded. Protect PDF is a free, browser-based tool in the Toolsnest pdf tools collection — there is nothing to install, no account to create and no watermark on your results. It works on desktop, tablet and mobile, and because the work happens on your own device it stays fast even with large inputs.
How to use the Protect PDF
- Open the Protect PDF — no sign-up or software download is required.
- Drag and drop your file(s) into the tool, or click to browse and select them from your device.
- Choose any options you need, such as order, quality, page range or output format.
- Click the action button and let the tool process everything locally in your browser.
- Download the finished file. Your originals are never changed or uploaded.
Why use the Protect PDF?
- 100% free with no limits, no sign-up and no watermarks.
- Private by design — your files are processed in your browser and never uploaded to a server.
- Fast and lightweight, with instant results even on a phone or a slow connection.
- Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
- Part of a full pdf tools suite, so related protect pdf tasks are one click away.
Is it private and secure?
Your privacy is built in. The Protect PDF does all processing on your own device using client-side code, so your files are never transmitted, stored or seen by anyone — including us.
Frequently asked questions
How does password protection work?
The PDF is encrypted with AES using your password. Anyone opening it must enter the password, and the encryption is done in your browser.
Can I recover a lost password?
No. There’s no backdoor — if you lose the password the file can’t be opened, so store it safely.
Does my file or password get uploaded?
No. Encryption runs locally with @cantoo/pdf-lib; nothing is sent to a server.