letradni is a free Chrome add-on developed by casado84 that allows you to easily calculate the control letter of any Documento Nacional de Identidad (DNI) or Número de Identificación de Extranjeros (NIE) in Spain. With this convenient tool, you can obtain the control letter without having to visit any specific website.

This Chrome add-on is a time-saving solution for individuals who frequently need to calculate the control letter for Spanish IDs and NIEs. By simply accessing the add-on from your browser's toolbar, you can quickly generate the correct control letter for any given ID or NIE.

letradni is a useful and efficient tool for anyone who deals with Spanish identification numbers on a regular basis. Its simplicity and accessibility make it a valuable addition to your Chrome browser, providing a hassle-free way to obtain the control letter for DNI and NIE numbers.