Drop your file here or
Choose files
Why lock PDF?
For more security, you can encrypt your PDF with a password to keep your document confidential. This will prevent unauthorized access to its content. Only people who know the password will be able to access your file.
Security & File Safety
Do you have concerns about the safety of your document? No worries, we will keep everything safe. In addition, every file will be deleted from the system.
Lock PDF with ease
Just upload your PDF and confirm the encryption. You’ll receive your new secured file in one click.
Best result
We use the best tools to make sure that you will get the expected result after encrypting or converting your files. With PDF Modify you can process your files in a few seconds and enjoy the result!
Available everywhere
View and transform your files on the go from everywhere. Your location and device no longer matter. All you need is just an internet connection.
Select a password
You should make sure that you will remember the password you entered or store it in a secure place. We don’t force you to use any specific format but keep in mind that the more complex the password is, the better protected your file will be.
How to Lock PDF:
  1. Upload your PDF file to PDF Modify by one of the following ways:
    • dragging a file from anywhere on your computer to the colored space on the page;
    • adding a file from your dropbox by clicking the ;
    • clicking the “Choose files” button.
  2. Type your password and click the “Lock PDF” button.
  3. Your new file is ready! Download it by clicking the “Download” button or add it to your Dropbox by clicking the .
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