The Spanish CIF (Código de Identificación Fiscal) is the tax identifier for companies and other legal entities. It is 9 characters long: an organisation-type letter, a 7-digit body, and a final control character that may be a digit or a letter. This validator checks the type and the control so you can catch a mistyped tax ID before submitting paperwork.
How it works
- Organisation letter. The first character must be one of the recognised types (A, B, C, D, E, F, G, H, J, N, P, Q, R, S, U, V, W).
- Control calculation. Across the 7-digit body, digits in odd positions (1st, 3rd, 5th, 7th) are doubled, and if the result exceeds 9 its digits are summed (equivalently, subtract 9). Even-position digits are added unchanged. The two are summed, and the control digit is
(10 − total mod 10) mod 10. - Digit or letter. That control digit maps to a letter via the table
JABCDEFGHI(index 0 = J, 1 = A, …). Types P, Q, R, S, N, W use the letter; A, B, E, H use the digit; all others accept either.
Example
For a CIF body of 5872073 under type A:
- Odd positions (5, 7, 0, 3) doubled → 10, 14, 0, 6 → digit-summed → 1, 5, 0, 6 = 12
- Even positions (8, 2, 7) → 8 + 2 + 7 = 17
- Total = 29 → control digit = (10 − 9) mod 10 = 1
So A58720731 is valid for a type that uses the digit form.
| First letter | Organisation type | Control form |
|---|---|---|
| A | Sociedad anónima (S.A.) | Digit |
| B | Sociedad limitada (S.L.) | Digit |
| P | Local authority | Letter |
| Q | Public body | Letter |
It runs entirely in your browser, so the number you type is never uploaded. A structurally valid CIF is not guaranteed to be one that has actually been issued.