PDF Encryption
Encrypt PDF
Protect your PDF documents with strong password encryption. AES-256, free and secure.
How to password-protect a PDF
- Upload the PDF you want to protect.
- Set a password (at least 4 characters; longer and mixed-character passwords are stronger).
- Download the encrypted PDF, which requires the password to open.
Why encrypt a PDF with Seleniun
- AES-256 password encryption, applied directly to the PDF.
- Only someone with the password can open the file.
- Free and processed without creating an account.
Common uses
- Protecting a document with personal or financial data before sending it.
- Restricting access to an internal report before it is shared more widely.
- Adding a password to a contract before emailing it.
Frequently asked questions about encrypting a PDF
What encryption does Seleniun use?
PDFs are protected with AES-256 password encryption.
What happens if I forget the password?
Seleniun does not store your password, so the encrypted PDF cannot be recovered without it. Keep it somewhere safe.
What is the minimum password length?
Passwords must be at least 4 characters; using letters, numbers and symbols makes them stronger.
Is my file kept after encryption?
No. The file and password are only used to generate the encrypted PDF and are not retained.
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