How to Password-Protect a PDF for Free
⏱ Takes less than 1 minute
Need to send a PDF securely? PDFredo's free online PDF protector encrypts any document with a password using AES-128 or AES-256. No account, no watermarks, and your file is deleted from our EU servers after 30 minutes.
Upload your PDF
Drag your PDF into the upload area or click "Select File". Files up to 100 MB are supported.
Set a password and permissions
Enter a strong user password (to open) and optionally an owner password (to control printing, copying, editing).
Download the protected PDF
Click "Protect PDF". PDFredo encrypts the file on secure EU servers and offers the protected version for download.
Pro Tips
- Use at least 12 characters with letters, numbers, and symbols for a strong password.
- Share the password through a different channel than the PDF (e.g., SMS for the password, email for the file).
- Keep a backup of the unprotected original. Lost passwords cannot be recovered.
Frequently Asked Questions
Is PDF password protection secure?
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AES-256 encryption is strong and widely accepted for business use. It is not unbreakable. Short or guessable passwords can still be cracked, so pick a long, unique password.
What is the difference between user and owner password?
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The user password is required to open the PDF. The owner password controls what readers can do (print, copy, edit) once opened.
Can I recover a lost password?
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No. PDFredo does not store your password. Lost passwords usually mean the file is unrecoverable.
Are my files private during processing?
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Files are processed on EU servers (Germany) and deleted automatically after 30 minutes. Your password is never logged.
Which encryption standard do you use?
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AES-128 by default and AES-256 on request. Both are standard for PDF encryption.
Is this really free?
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Yes. No registration, no subscription, no watermarks.
Does it work on mobile?
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Yes. Any modern browser on iOS and Android.