Privacy-first document tools
Protect PDF online
Lock PDF files online and add password protection before sharing. Use privacy-first PDF security tools from LeafDeck.
What this tool does
Lock PDF adds password protection to a PDF before you share it. It is useful for contracts, personal documents, internal files, financial papers, or any PDF that should not be opened casually by the wrong person.
- Add password protection to PDFs
- Restrict casual access before sharing
- Useful for private or sensitive documents
How to use this tool
Choose a compatible source file
Open Protect PDF and select the file format described by the upload area. Keep the original until the new file has been checked.
Run Protect PDF
Encrypt PDF with a password. Review any available settings before processing so the output matches the way you plan to use it.
Download and compare
Open the result and compare page count, orientation, text, images, dimensions, and formatting with the source before sharing it.
When Protect PDF is useful
Everyday document work
Lock PDF adds password protection to a PDF before you share it. It is useful for contracts, personal documents, internal files, financial papers, or any PDF that should not be opened casually by the wrong person.
Compatibility and sharing
Use Protect PDF when the source format is inconvenient for the recipient, upload portal, device, or next step in your workflow.
Create a separate working copy
The downloaded result is a new file, so the original remains available as a reference while you inspect the conversion or edit.
Review the Protect PDF output
A successful Protect PDF operation should solve the format or document task without hiding important information. Open the downloaded file rather than relying only on its filename or file size.
Check small text, images, page order, orientation, transparency, links, forms, annotations, and uncommon fonts whenever those features matter. Keep the source file until the result has passed that review.
Frequently asked questions
How do I password protect a PDF?
Upload the PDF and apply a password so the document is harder to open without authorization.
Why should I lock a PDF?
Locking a PDF adds a basic layer of protection when you need to share a file that contains sensitive or private information.
Can I protect a PDF before emailing it?
Yes. Password-protecting a PDF before sending it is a common way to reduce casual access risk.