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Protect PDF
Add a password to your PDF
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Drop .pdf files here
or click to browse
How it works
- 1. Upload your .pdf file
- 2. Enter your email address
- 3. Download your converted file
About Protect PDF
Protecting sensitive documents with a password ensures that only authorised recipients can open them. PDF Ninjas adds password protection to your PDF so that anyone who receives it will need the correct password to view the content. Perfect for financial documents, confidential reports, legal agreements, and any file you want to share securely.
Frequently Asked Questions
What happens if someone tries to open the PDF without the password?▾
They will be prompted to enter a password and cannot access the content without it.
How strong is the password protection?▾
Password protection is applied using PDF standard encryption. The security level depends on the strength of the password you choose — use a long, unique password for best protection.
Can I remove the password later?▾
Yes — use the Unlock PDF tool on PDF Ninjas to remove the password, as long as you know the original password.
Will the file content be changed?▾
No — only the access restriction is added. The original content, formatting, and quality remain unchanged.