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Protect PDF
Encrypt your PDF with a password to keep sensitive data confidential.
or drop files here
Processed locally in your browser — nothing is uploaded.
How to Protect PDF
- Choose your file or drop it into the box above.
- Adjust the options if you need to.
- Click the button and download your result.
Frequently asked questions
Is Protect PDF free?
Yes. Protect PDF on PDF Sky is completely free, with no limits, no watermarks and no sign-up.
Are my files uploaded to a server?
No. Your files are processed directly in your browser and never leave your device.
Does it work on my phone?
Yes. PDF Sky works in any modern browser on Windows, Mac, Linux, iPhone and Android.