How do I password protect a PDF for free online?

Open the ClearwayPDF lock tool, add your PDF, set an open password and optionally a permissions password, then click Protect and Download.

What is the difference between an open password and a permissions password?

An open password (user password) is required to open and view the PDF. A permissions password (owner password) restricts actions like printing, copying, and editing without changing the ability to view it.

Can the password be removed by someone else?

The PDF is encrypted using standard PDF encryption. The password cannot be removed without the correct permissions password and appropriate software.

Is my PDF uploaded to a server when adding a password?

No. Password protection runs entirely in your browser using pdf-lib. Your file never leaves your device.

What encryption does ClearwayPDF use to lock PDFs?

ClearwayPDF uses standard PDF encryption (RC4/AES) as supported by the PDF specification, compatible with Adobe Acrobat and other PDF readers.

← Back to home

Lock PDF

Password Protect PDF Free Online — Lock Any PDF Instantly

Add a password to any PDF in seconds. Set an open password to restrict viewing, or a permissions password to prevent printing and editing. No upload, no account.

Lock a PDF now →

How it works

Three steps, done.

Step 1

Open the Lock PDF tool

Go to ClearwayPDF and open the Password Protect tool.

Step 2

Upload your PDF and set a password

Upload your PDF and type the password you want to use. Optionally set a permissions password too.

Step 3

Download the protected PDF

Click Protect, then Download. Your password-protected PDF is saved to your device.

What you get

Everything included, nothing locked

Open password protection

Require a password to open and view the PDF. Anyone without it sees nothing.

Permissions password

Optionally set a separate password to restrict printing, copying, and editing while allowing viewing.

Standard PDF encryption

Uses PDF-standard encryption compatible with Adobe Acrobat, Preview, and all major PDF readers.

Fully private

Password protection happens entirely in your browser. Your file and password never leave your device.

No account needed

Protect your PDF immediately without signing up or providing personal information.

No watermarks

The protected PDF is clean. No ClearwayPDF branding or stamps are added.

Why ClearwayPDF

Free, private, no strings attached

No subscription or paywall
No file uploads — fully private
No watermarks on output
No account or login needed
Standard PDF encryption
Free to use

Try it free →

Guides

Guides for this tool

Lock PDF

PDF password protection explained

Understand open passwords, permissions passwords, and what PDF encryption can and cannot protect.

5 min readRead

Privacy

Are online PDF editors safe?

How to evaluate privacy, browser-based processing, cookies, and risk before using a PDF editor on sensitive documents.

7 min readRead

Watermark PDF

How to add a watermark to a PDF

Mark a PDF as a draft, confidential or a copy with a text watermark, and choose wording, colour and opacity that stay readable.

4 min readRead

FAQ

Frequently asked questions

How do I password protect a PDF for free online?: Open the ClearwayPDF lock tool, add your PDF, set a password, then click Protect and Download.
What is the difference between open and permissions passwords?: An open password restricts who can view the PDF. A permissions password restricts actions like printing and editing without blocking viewing.
Can someone remove the password?: The PDF uses standard encryption. The password cannot be removed without the correct permissions password and appropriate software.
Is my PDF uploaded to a server?: No. Everything runs in your browser. Your file and password never leave your device.
What encryption is used?: Standard PDF encryption (RC4/AES) compatible with Adobe Acrobat, Preview, and all major PDF readers.