Encrypt your PDF with a user password so only authorized people can open it. 100% browser-based — your files stay private on your device.
Password-protecting a PDF means encrypting the file so that anyone who tries to open it must first enter the correct password. This is one of the most effective ways to prevent unauthorized access to sensitive documents — from personal identification documents to confidential business reports.
Compressfy's free PDF protection tool uses the pdf-lib library to apply AES-based encryption entirely within your browser. No document data ever passes through our servers. The resulting PDF is fully compatible with Adobe Acrobat, PDF readers on iOS and Android, and any standard PDF viewer.
Use at least 12 characters combining uppercase letters, lowercase letters, numbers, and symbols. Avoid obvious words like your name, date of birth, or "password123". Consider using a passphrase — a random string of words — which is both strong and memorable. Always store the password in a secure password manager.
If you ever need to remove a password from a PDF, use our Unlock PDF tool. And if you simply need to merge protected PDFs together, use our Merge PDF tool after unlocking them.