Spanish CCC Check Digit Calculator

How Spanish CCC Check Digit Calculator Works?

The Spanish CCC Check Digit Calculator works by computing 2 control digits (DC) with weights 1, 2, 4, 8, 5, 10, 9, 7, 3, 6 and modulus 11: the first over the bank and branch codes, and the second over the 10-digit account number.

1. 1Enter the 4-digit bank code (entidad), the 4-digit branch code (oficina), and the 10-digit account.
2. 2Prefix 00 to bank + branch to make 10 digits.
3. 3Multiply the 10 digits by 1, 2, 4, 8, 5, 10, 9, 7, 3, 6 and compute 11 − (S mod 11).
4. 4Convert 11 to 0 and 10 to 1 for the first control digit.
5. 5Repeat over the 10-digit account for the second control digit.

Spanish CCC Check Digit Calculator Formula

The Spanish CCC formula is DC = 11 − (Σ dᵢ·wᵢ mod 11), with 11 → 0 and 10 → 1, applied twice.

w = 1, 2, 4, 8, 5, 10, 9, 7, 3, 6   (wᵢ = 2ⁱ⁻¹ mod 11)
DC₁ = g(11 − (Σ (00‖bank‖branch)ᵢ·wᵢ mod 11))
DC₂ = g(11 − (Σ accountᵢ·wᵢ mod 11))
g(11) = 0, g(10) = 1

• DC₁ protects bank and branch.
• DC₂ protects the account number.

First digit: 0021000418 → weighted sum 95 → 11 − (95 mod 11) = 4 → 4
Second digit: 0200051332 → weighted sum 105 → 11 − (105 mod 11) = 5 → 5
CCC = 2100 0418 45 0200051332
IBAN = ES91 2100 0418 4502 0005 1332

Spanish CCC Check Digit Calculator Conversion Table

The Spanish CCC conversion table lists bank, branch, and account combinations with their 2 control digits.

What is Spanish CCC Check Digit Calculator?

A Spanish CCC Check Digit Calculator is a tool that computes the 2 control digits (dígitos de control) of a 20-digit Código Cuenta Cliente (CCC). The CCC was the Spanish domestic account format before IBAN.

The 20-digit CCC sits unchanged inside every Spanish IBAN after the ES prefix and IBAN check digits.

What are the uses of Spanish CCC Check Digit Calculator?

There are 3 main uses of the Spanish CCC Check Digit Calculator, including IBAN creation, direct debit mandates, and legacy data checks.

• IBAN creation: Spanish banks and businesses build ES IBANs from CCC numbers.
• Direct debit mandates: Billers validate account numbers on SEPA mandates.
• Legacy data checks: Data teams verify CCCs stored before 2014.