How secure is the password protection?

We use industry-standard PDF encryption. The password is applied client-side using pdf-lib, so your file and password never leave your browser.

Can I remove a password later?

You'll need the password to open the PDF. Use our PDF Password Remover tool if you know the password and want to remove protection.

ThePDF

Add password protection to your PDF files — 100% client-sideUpdated 2026-03-16

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Drop your PDF here or click to browse

Files are processed locally — never uploaded

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Drag & drop your file here or click to browse

Password

Confirm Password

🔒 All encryption happens in your browser using pdf-lib. Your PDF and password are never sent to any server.

All encryption happens locally in your browser. Your file and password are never uploaded to any server.

Is PDF Password Protector free to use?

Yes, completely free. No signup, no limits. All processing happens in your browser — your files never leave your device.

How secure is the encryption?

We use pdf-lib to apply standard PDF encryption. Your password and file never leave your browser, making it completely private.

Does it work on mobile?

Yes, it works on all devices including phones and tablets. The interface is fully responsive.

Is my data safe?

Absolutely. Everything runs locally in your browser using JavaScript. No data is uploaded to any server.

Cite this tool:

"PDF Password Protector." ThePDF, the-pdf.com, https://the-pdf.com/tools/pdf-password-protector/. Accessed 2026-03-16.