Lock PDF
Add a password to open your PDF, or restrict editing and printing — keeping your document under your control.
Tool not loading? Open Lock PDF in full ↗
When a document is sensitive, you want control over who can open it and what they can do with it. Locking a PDF lets you require a password to open the file, and optionally stop others from editing or printing it. PdfMind.io applies strong encryption and returns your protected file in seconds.
How to lock a PDF
- Choose your PDF file in the tool above.
- Set a password to open the file, and/or tick Restrict editing or printing.
- Download your locked PDF.
Why use PdfMind.io
- Strong AES-256 encryption for the open password.
- Optionally restrict editing, copying and printing.
- Free to use, with no watermark.
- Your file is processed securely and deleted right after.
Frequently asked questions
How strong is the password protection?
The open-password uses AES-256 encryption, the modern standard used by tools like Acrobat.
What's the difference between a password and restrictions?
A password is needed to open the file at all; restrictions let anyone open it but limit editing or printing.
Are edit and print restrictions unbreakable?
They are honoured by standard readers like Acrobat, but like all PDF permission flags they are not absolute encryption. The open-password is the truly strong lock.
Is Lock PDF free?
Yes, it's free with no sign-up.