Calculate DNI letter

This simple app calculates the Spanish Id (DNI - Documento Nacional de Identidad) letter.

Spanish id number is composed by a 7-8 numbers and a letter (ie: 441234567 F)

With this app you just need to enter the numbers and it will provide you the letter that belongs to that number.

Ideal if you need to check the Spanish Id number of a customer.

The app interface is in Spanish.