Lock PDF
Password protect your PDF file. Add encryption to prevent unauthorized access to your sensitive documents.
Drop your PDF here
or click to browse or
Max 100 MB
How to lock pdf
- 1
Upload PDF
Select the PDF document you want to secure with password encryption.
- 2
Set Password
Enter a strong password to lock the document.
- 3
Secure
Click the Lock PDF button to encrypt the file.
- 4
Download
Download your password-protected PDF.
About the Lock PDF
PDF supports built-in password encryption at the file-format level, meaning the protection travels with the file itself rather than depending on wherever it's stored — unlike, say, a password-protected folder that only protects the file while it stays in that folder. Once encrypted, no PDF viewer can open the document's content without the correct password, regardless of what platform it ends up on.
This is the standard way to add a layer of protection to a document containing sensitive information — financial statements, ID copies, HR records — before emailing it or uploading it somewhere less trusted than your own storage. Set a password here and the resulting PDF requires it to open in any standard PDF reader.
Frequently Asked Questions
What encryption is used?
PDFs are encrypted using AES-256 encryption, the industry standard for PDF security.
Can I set different user and owner passwords?
Currently the same password is used for both. Advanced options are coming soon.
What is the minimum password length?
Passwords must be at least 4 characters long.