Protect PDF
Lock your PDF with a password so only the right people can open it.
Tap to choose a file
How it works
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Choose or drop the PDF you want to lock.
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Type the password — it's required, so pick one you'll remember.
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Click Protect PDF.
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Download the encrypted file and share the password separately.
Frequently asked questions
Do I have to set a password?
Yes — a password is required, since it's what encrypts the file. Anyone opening the PDF afterwards will be asked for it, so share it with recipients through a separate channel.
Which encryption strength should I pick?
256-bit AES is the strongest and works in all modern PDF readers — use it unless a recipient is stuck on a very old reader, in which case 128-bit is more compatible.
What if I forget the password?
There's no recovery — the encryption is real, and we never store your password. Keep a copy of the password (or the original unprotected file) somewhere safe.
What happens to my file?
It's processed on our server and automatically deleted within 1 hour. We never read or share your documents, and the password is used only to encrypt the file.
What's the maximum file size?
100 MB per PDF.
Related tools
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Password Generator
Cryptographically random passwords with a real entropy meter — generated on your device.