Yes. Unlimited use, no registration and no watermark.

Protect PDF with Password — Free Online

Protect PDF adds a user password so the document can only be opened by people who know the password. Encryption is applied locally in the browser. Perfect for contracts, personal records or any document you want to share securely. Free, unlimited, no registration, no watermark.

Open Protect PDF tool now

Step-by-step instructions

Open Protect PDF.
Upload the PDF.
Enter and confirm a strong password.
Download the password-protected PDF.

Supported formats

PDF (.pdf).

Privacy & security

Files are processed locally in your browser. We do not operate an upload endpoint for this tool. Temporary data is released when you leave the page. The site is served over HTTPS. See our Privacy Policy.

Pricing & workflow

Price: Free forever — no limits, no watermark. Workflow: open tool → add file(s) → process in browser → download. Works offline for most operations once libraries are loaded. Compatible with Chrome, Edge, Firefox and Safari on desktop and mobile.

Frequently asked questions

Is Protect PDF free?

Yes. Unlimited use, no registration, no watermark.

Are my files uploaded?

No. Processing is 100% in-browser.

Can I use it on mobile?

Yes, on modern mobile browsers.

Is there a file size limit?

We do not set a server limit. Practical limits depend on your device memory.

Does it add a watermark?

No. Output contains only your content.