Get the OCR codes from the back of the Spanish ID Card.
The National Identity Document of Spain (DNI) is a document the size of a credit card issued by the Ministry of the Interior through the National Police, which certifies the identity and personal data of its holder, as well as his Spanish nationality.
At the bottom of the back of the DNI there are a series of OCR-B characters intended to be read mechanically according to ICAO regulations for documents.
These characters correspond to the data that appears on the front, such as the support number, the dates of birth and validity of the document, the name and surname or the ID number itself.
Between these OCR characters there are 4 control numbers (highlighted in red or green in the application).
One of them is the famous lonely number at the end of the second line.
This application calculates these numbers based on the data entered, thus demonstrating that they do not correspond to what certain urban legends say.
The application works both for the DNI 2.0 distributed since 2006 and for the new DNI 3.0 issued since 2015.
Don't hesitate to try it.