How to Password Protect a PDF for Free
Add a password to any PDF instantly — secure, private, and entirely in your browser. Protect your sensitive information without Adobe Acrobat.
Step-by-Step Security Guide
Step 1 — Open the Protect PDF tool
Go to our Protect PDF tool. It uses pdf-lib to encrypt the file entirely inside your browser — no server communication of any kind.
Step 2 — Upload your PDF
Drag and drop your PDF into the upload zone, or click to browse. The file loads locally — even massive documents are processed instantly since nothing is transmitted.
Step 3 — Set your password
Type your chosen password in the password field. For strong security, use at least 12 characters combining uppercase, lowercase, numbers, and symbols. The tool shows a password strength indicator in real time.
Step 4 — Encrypt and download
Click "Protect PDF". The tool encrypts your document with AES-256 and immediately offers the protected version for download. Test it by opening the downloaded file — you'll be prompted for the password.
Frequently asked questions
Can I add a password to a PDF without Adobe Acrobat?
Yes. Our free browser-based tool lets you encrypt any PDF with a password without installing Adobe Acrobat or any other software.
What encryption does the tool use?
The tool uses high-grade encryption — the same standard used by professionals to secure documents. It's safe and reliable for sensitive data.
Does my PDF get uploaded to your servers?
Never. The encryption runs entirely inside your browser. Your PDF never leaves your device.
Protect your sensitive PDF right now
Add AES-256 encryption to any PDF in seconds — completely free, no uploads, no Adobe required.
🔒 Add Password to PDF — Free