PDF Password Protector Online Free — Add Password to PDF
Encrypt any PDF with a user password and optional owner password to control printing, copying, and editing permissions. Or remove an existing password from a PDF you own. All encryption runs locally in your browser using @cantoo/pdf-lib — your file never leaves your device.
Frequently Asked Questions
What is the difference between a user password and an owner password?
A user password (also called an open password) is required to open and view the PDF. An owner password controls permissions — it allows the document creator to restrict printing, copying, editing, or annotating even for users who can open the file. If you set only a user password, the owner password defaults to the same value.
What permissions can I control?
You can individually control: printing (high resolution or none), copying text and images, editing the document content, and adding annotations/comments. These are standard PDF permission flags specified in the PDF specification and respected by Adobe Acrobat and most PDF readers.
Is my PDF uploaded to a server?
No. All encryption and decryption is performed locally in your browser using the @cantoo/pdf-lib JavaScript library. Your PDF file bytes never leave your device. Privatool servers are not involved in processing.
Can I remove a password from a PDF I don't own?
This tool can only remove the password if you know the current password. It does not crack, brute-force, or bypass PDF encryption. You must supply the correct password to decrypt and re-save the file without protection.
What encryption standard is used?
The tool uses AES-256 encryption when encrypting PDFs, which is the standard for PDF 2.0 and is supported by all modern PDF readers. This provides strong protection against unauthorized access.
What makes a strong PDF password?
A strong password should be at least 12 characters long and include uppercase letters, lowercase letters, numbers, and special characters (like !, @, #, $). Avoid dictionary words, names, or dates. The password strength indicator in the tool scores your password in real time across 5 levels.