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Protect PDF with a password
Encrypt a PDF with an open password and choose whether printing, copying or editing stays allowed.
- No installation
- AES-256 encryption
Protect PDF with a password
Protect a PDF with a password and AES-256.
At least 4 characters. 12 or more characters mixing letters, digits and symbols is a good choice.
Note: accented letters and other non-ASCII characters do not work in every PDF reader.
Lets you lift the restrictions later. It must differ from the open password.
Without your own permissions password, we set a random one. The restrictions can then no longer be lifted, so keep the original file.
Encrypted with AES-256. Current PDF readers open the file once the password is entered.
Your files are only used for this tool and are deleted automatically afterwards.
Protect a PDF in three steps
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Choose the file
Drop a PDF file into the box or choose it. If it is already protected, enter its password first.
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Set password and rights
Choose an open password and decide whether printing, copying or editing stays allowed.
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Protect and save
Click "Protect PDF" and download the encrypted file.
Password-protect PDF files
What the password protection does
The PDF file is encrypted with AES-256. Anyone who wants to open it needs the password. Without it, text and images cannot be read, not even with a different program.
You can also restrict rights such as printing or copying. Most PDF readers respect these restrictions. They are not protection against deliberate circumvention, though: anyone who can open the file can save it without restrictions using suitable tools.
Good passwords
- At least 12 characters, ideally several random words in a row
- No names, birth dates or single dictionary words
- Share the password separately from the file, for example by phone
- Do not reuse the password of other files for confidential documents
Good to know
If the file is already protected, open it with its password first. Your new settings then replace the existing protection. Encrypted files cannot be PDF/A at the same time, so an existing PDF/A marking is removed.
FAQ
Questions about protecting PDF files
What happens to my PDF file?
Your file is only used for encryption and is deleted automatically afterwards.
How secure is the protection?
The file is encrypted with AES-256. How secure it is depends mainly on the password: long, random passwords are practically impossible to guess, while short or common words are not.
What is the difference between the open password and the permissions password?
Everyone who wants to read the file needs the open password. The permissions password lets you lift restrictions such as printing or copying later. If you restrict rights without setting your own, the tool sets a random one.
Can I re-protect a PDF that is already protected?
Yes, if you know its current password. Enter it in the file list. Your new settings then replace the old protection.
I forgot the password. Can it be recovered?
No. The password is not stored anywhere and cannot be recovered. Keep the original file and the password in a safe place.
More with PaperOffice AI
Send protected, with proof
With audit-safe email delivery in the AI-DMS, every PDF gets its own recipient password. The recipient gets a secure download link, and every step is logged.
- Individual PDF password per recipient, automatic on sending
- Password by email or separately by SMS
- Log of delivery, opening and download with time and place
- Revoke any time, proof PDF after the download
