🇪🇸 Spanish ID Letter Calculator
Compute the letter of your Spanish DNI or NIE with the official algorithm (modulo 23), or validate a full ID.
Frequently asked questions
How is the DNI letter computed?
The 8-digit number is divided by 23 and the remainder (0–22) is looked up in the official table TRWAGMYFPDXBNJZSQVHLCKE.
What about the NIE letter?
The initial letter is replaced by a number (X→0, Y→1, Z→2) and the same modulo 23 is applied to the resulting 8-digit number.
Does the letter distinguish people?
Yes: number + letter uniquely identify each citizen. Two people never share the same DNI.