Meaning of DNI Letters - Complete Table and Explanation

The DNI letters are part of a verification system that helps detect errors in the transcription of the number. Each letter has a specific mathematical meaning and its assignment follows a precise algorithm.

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Complete table of DNI letters

T
Remainder: 0
Frequency: Medium
R
Remainder: 1
Frequency: High
W
Remainder: 2
Frequency: Low
A
Remainder: 3
Frequency: Very high
G
Remainder: 4
Frequency: Medium
M
Remainder: 5
Frequency: High
Y
Remainder: 6
Frequency: Low
F
Remainder: 7
Frequency: Medium
P
Remainder: 8
Frequency: High
D
Remainder: 9
Frequency: Very high
X
Remainder: 10
Frequency: Low
B
Remainder: 11
Frequency: High
N
Remainder: 12
Frequency: Medium
J
Remainder: 13
Frequency: Medium
Z
Remainder: 14
Frequency: Low
S
Remainder: 15
Frequency: High
Q
Remainder: 16
Frequency: Low
V
Remainder: 17
Frequency: Medium
H
Remainder: 18
Frequency: Medium
L
Remainder: 19
Frequency: High
C
Remainder: 20
Frequency: High
K
Remainder: 21
Frequency: Low
E
Remainder: 22
Frequency: High

Most common letters

The most frequent letters in Spanish DNIs are:

  • A, D: Very high frequency
  • R, M, P, B, S, L, E, C: High frequency
  • W, Y, X, Z, Q, K: Low frequency

Excluded letters and reasons

I

Excluded to avoid confusion with the number 1

Ñ

Excluded because it is a non-universal special character

O

Excluded to avoid confusion with the number 0

U

Excluded to avoid confusion in handwriting

Curiosities about DNI letters

  • 23 letters of the Spanish alphabet are used
  • The distribution is not random, it follows a mathematical pattern
  • The most common letters correspond to more frequent division remainders
  • The system has remained unchanged since 1962

Frequently asked questions

Why does my DNI have that specific letter?

The letter is mathematically assigned by dividing the number by 23 and using the remainder to determine the corresponding letter.

Can I choose my DNI letter?

No, the letter is determined by the algorithm and it is not possible to choose it.

Are some letters "better" than others?

No, all letters have the same validity. Their only function is to verify the correct transcription of the number.