Protect PDF
Lock a PDF with a password (AES-256).
How to protect PDF
Encrypt a PDF with a password using AES-256 and control printing, copying and editing permissions. Free, private, no upload.
- 1
Drop a PDF.
- 2
Set a password and permissions.
- 3
Download the protected PDF.
Private
Nothing is uploaded
Instant
No queues or waiting
Free
No sign-up, no watermark
Frequently asked questions
How strong is the encryption?
Dropkit uses AES-256, the strongest encryption supported by the PDF standard, powered by the open-source qpdf engine.
Are my files uploaded to a server?
No. Dropkit processes everything locally in your browser using WebAssembly. Your files never leave your device, which also makes it faster — there's nothing to upload or download.
Is it free?
Yes. All browser-based tools are free with no sign-up and no watermarks. A Pro plan with unlimited batches, saved workflows and server-powered Office conversions is coming soon.
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