Protect a PDF with a password

How to use it

1. Select your PDF, or drop it onto the box.
2. Enter your chosen password, then enter it again to confirm.
3. Click Protect PDF, then save the locked copy.

The strength of the lock

Your locked copy uses 256-bit AES encryption, the highest level of protection the PDF format provides, and any up-to-date PDF reader will open it once the password is entered. Even so, the lock can only be as strong as the password behind it. A long phrase made of several words is much harder to guess than a single short word followed by a number.

You can also ask PDF readers to block printing or copying of the text. Most readers go along with this, but some do not, so treat it as a polite request rather than a lock. What really protects the document is the password needed to open it.

Looking after the password

If you forget the password, there is no way to get it back, and TeddyPDF cannot help, because it never sees it. The password is used within your browser and discarded once you close the page. When sharing the file, send the password by a different route, such as a text message, rather than in the same email as the document.

Bear in mind that a password keeps out people who do not have it. It cannot stop someone who does have it from passing on the document or its contents, so share it only with people you would trust with what the file says.

Questions and answers