Protect PDF
Add password protection to secure your PDF document.
Processed in your browser — files never uploaded
Drop your PDF file here
or click to browse
Max file size: 100MB
Set a password to protect your PDF
Protect PDF online, free and secure
Add a password and encryption to a PDF so only people with the password can open it. Protect contracts, financial records, and sensitive files before sharing them — encryption is applied in your browser.
How to protect pdf
Upload your PDF
Select the PDF you want to secure.
Set a password
Choose a strong password that will be required to open the document.
Download the protected PDF
Save the encrypted file; it now requires the password to open.
Why use Kobra PDF to protect pdf
- Password-protect sensitive documents
- Strong encryption applied locally
- Keeps confidential files private when shared
Protect PDF — frequently asked questions
- What kind of protection is applied?
- The PDF is encrypted and locked with the password you set, so it cannot be opened without it in any standard PDF reader.
- What happens if I forget the password?
- There is no recovery — that is the point of encryption. Store the password somewhere safe, because we do not keep a copy.
- Can I remove the password later?
- Yes. If you know the password, use the Unlock PDF tool to remove protection.
- Is my file uploaded during protection?
- No. Encryption is applied in your browser, so your document is never sent to a server.