Protect PDF with Password — AES-256 Encryption Online
Add password protection to a PDF file.
FAQ
Protect PDF — frequently asked questions
How strong is the password protection?
The PDF is encrypted with AES-256, a strong modern standard. Anyone opening the file needs the password you set.
What if I forget the password I set?
It cannot be recovered; there is no reset. Keep the password somewhere safe and keep an unprotected copy of the original file.
Can I remove the password later?
Yes. Use the Unlock PDF tool with the password you set and download an unprotected copy.
Is my file uploaded? Is Protect PDF safe to use?
Protect PDF needs our processor to do the conversion, so your file travels over an encrypted HTTPS connection to a private temporary folder. It is deleted automatically when the download finishes or you leave the page, and we never read, keep or share it.
Is Protect PDF free? Is there a file size limit?
Yes, it is free with no account, signup or watermark. Very large files can be rejected or take longer, so split or compress them first if the upload does not go through.
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