Protect a PDF with a password
Protect PDF locks your document with a password. Without it, the file can't be opened at all — not in a browser, not in Acrobat, not on a phone. The encryption is AES-256, the strong standard used by banks and governments.
The password is required to open the document. Once opened, it can be read and printed normally. Keep a copy of the unprotected original in a safe place on your own device, and use a password manager if you protect many documents.
A password-protected PDF is the simple way to email payslips, medical results, tax documents or contracts, because a misdirected email or a lost USB stick no longer exposes the content. Send the password through a different channel — a text message or a phone call — not in the same email.
Encryption runs on our secure server. Your file is encrypted in transit and at rest, and deleted right after download, never kept longer than 10 minutes. We never see or store your password. Choose it carefully: we can't recover it for you.
Drop a PDF here
PDF · or click to choose · you can also paste · up to 300 MB · stays on your device
Your privacy
Your file is sent over an encrypted connection and processed in an isolated sandbox. Files are encrypted, deleted right after download, and never kept longer than 10 minutes. We never look at, share or keep copies of your files.
How to use Protect PDF
- 1
Add your PDF
Drop the file on the page or click to choose it.
- 2
Choose a password
Type it twice. Use at least 10 characters that aren't easy to guess.
- 3
Protect and download
Save the locked PDF and share the password separately.
Questions and answers
How strong is the protection?
The PDF is encrypted with AES-256. With a good password it can't be opened without it.
What if I forget the password?
We can't recover it — it isn't stored anywhere. Keep your original unprotected file somewhere safe.
Is my file safe on your server?
Files are encrypted, deleted right after download, and never kept longer than 10 minutes. We never look at, share or keep copies of your files.
How do I remove the password later?
Use Unlock PDF with the password you set.
What's the size limit?
One file up to 100 MB and 500 pages.