Protect PDF
Encrypt and secure your PDF documents with passwords.
Select PDF to Protect
Add a password securely. All processing happens in your browser.
How to password protect a PDF file online
Upload your PDF
Click the Select PDF button or drag and drop your file into the box.
Set a password
Enter a strong user password. This will be required to open the document.
Apply encryption
Click the Protect button. We use AES-256 encryption for maximum security.
Download
Save your newly secured PDF file immediately to your device.
Frequently asked questions
Is it safe to protect my PDF on Nextooly?
Yes. All encryption happens locally in your browser using WebAssembly. Your files and passwords are never sent to our servers, ensuring 100% privacy.
What type of password am I setting?
You are setting a document-open password. Once applied, anyone who tries to open the file will be prompted to enter this password before they can view the content.
What encryption standard do you use?
By default, we use AES-256 (Advanced Encryption Standard with a 256-bit key), which is the industry standard for securing sensitive data.
Can you recover my password if I lose it?
No. Because we respect your privacy and do not store your data, we have no way to retrieve or reset a forgotten password. Please keep your password safe.
Can I protect a file that already has a password?
No. If a file is already locked, you must first use our Unlock PDF tool to remove the old encryption before applying a new password here.
More PDF tools
Compress PDF
Reduce PDF size while keeping text sharp and selectable.
Edit PDF
Add text, signatures, shapes, redactions, and quick text fixes in your browser.
Unlock PDF
Remove a known PDF password privately without uploading the file.
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