Digital IDs are very safe provided you keep your private key and password to yourself. Think of your password as a key to a safe. If you are the only person with the key, the safe's contents are secure. However, if you share the key with others, you lessen the security of the safe contents.

If anyone gets your Digital ID, they cannot use it unless they have the matching private key and the password to the private key. Before your Web browser sends your Digital ID, the browser prompts you for your password. You must enter the password before your Digital ID is used.

Digital IDs also come in various strengths. The lowest strength is called "40-bit," which refers to the size of the key for the ID. The highest strength is called "128-bit." If a 40-bit key can be deciphered in 4 hours, it would take longer than the age of the universe to crack a 128-bit key.