Protect PDF

Add a password to your PDF to prevent unauthorized access.

Loading tool...

How to use Protect PDF?

Select a PDF that is not already password-protected (or drag and drop it).
Enter a password and confirm it (at least 4 characters).
Click Lock PDF and download your protected file.

YouTube video

Tutorial video coming soon.

FAQs

Is my PDF secure while I protect it?

Yes. Protect PDF runs entirely in your browser on your device. Your PDF is not uploaded to our servers for processing, and we do not store your file or password. The site loads over HTTPS like any secure webpage, but the protection step itself happens locally.

What happens if I forget my PDF password?

PrivOffice never stores your password, so we cannot recover it for you. Keep a copy in a safe place. If you lose the password, you will need the original unprotected PDF (or another backup) to create a new protected version.

Can I protect a PDF without setting a password?

Not in this tool. Protect PDF requires a password (minimum 4 characters) and applies standard encryption together with permission settings. To use only restrictions without an open password, you would need different software that supports that workflow.

What permissions does the locked PDF use?

The protected file requires your password to open. Printing is allowed at high resolution; copying, editing, annotating, form filling, and document assembly are restricted, while content accessibility for assistive tools remains enabled—matching the fixed policy built into PrivOffice Protect PDF.

Will the protected PDF open in all PDF readers?

It uses standard PDF password encryption, so it should open in common apps such as Adobe Acrobat, Preview on Mac, and most browser PDF viewers, as long as they support encrypted PDFs. Very old or unusual viewers might behave differently.

Is there a file size limit?

There is no separate server limit because files are processed in your browser. Very large PDFs use more memory and may be slower or fail on low-powered devices; typical document sizes usually work fine.

Can I remove protection later?

Yes. If you know the password, use PrivOffice’s Unlock PDF tool to decrypt the file and lift the restrictions.

My PDF is already password-protected. Can I add a new password?

Use Unlock PDF first with the current password to get an unprotected copy, then use Protect PDF on that file with your new password.

Is Protect PDF free?

Yes. It’s free to use with no sign-up required.

Blogs

Featured

How to Use Protect PDF - Free Online Tool

Password-protect your PDF files. Our Protect PDF tool lets you add a password to prevent unauthorized access. Essential for sensitive documents.…

Getting Started with PrivOffice - Free Document Tools

PrivOffice is a professional suite of document utility tools. Secure, fast, and free.…

Complete Guide to PDF Tools - Merge, Split, Convert & More

PrivOffice offers 20+ PDF tools for every need. Merge multiple PDFs into one, split PDFs by page range, compress file size, convert images to PDF, extract text,…

How to Use Open PDF - Free Online Tool

Open PDF is a powerful tool in the PrivOffice suite. It helps you accomplish document tasks quickly and securely.…

How to Use Merge PDF - Free Online Tool

Merging multiple PDF files into a single document is a common need for professionals and students alike. Whether you're combining reports, merging scanned docum…

How to Use Split PDF - Free Online Tool

Need to extract specific pages from a PDF? Our Split PDF tool lets you separate a PDF into individual pages or custom ranges. Perfect for sharing only relevant …

How to Use JPG to PDF - Free Online Tool

Convert JPG, PNG, WebP, and other image formats to PDF in seconds. Our Images to PDF tool supports multiple images per document, with options for page size, ori…

Why use PrivOffice?

The same benefits apply to every tool—including Protect PDF.

Secure & private

Your files are processed in your browser on your device—not sent to our servers for processing or kept on our systems. Sensitive documents stay under your control.

100% free

No hidden fees, no premium tiers, and no usage limits. Use PrivOffice for personal or business work—no account required.

Fast processing

Tasks run locally in your browser so you get results quickly—often in seconds—without waiting on a remote queue, even for larger files your device can handle.

Works everywhere

No software to install. Open PrivOffice in any modern browser on Windows, Mac, Linux, iOS, or Android and use the tools you need.

Safe in our hands

PrivOffice takes security very seriously. Remember that your files stay on your device—processing runs in your browser, and we don’t store your documents on our servers.