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Tool to check BBAN numbers. The BBAN (Basic Bank Account Number) algorithm allows to check if a BBAN number is correct.

Answers to Questions

What is a BBAN?

A BBAN (Basic Bank Account Number) is composed of 10 to 30 characters, depending on countries, corresponding to the bank codes (including the account number) and a checksum key.

How to verify an BBAN number? (Validity check)

The algorithm checks the BBAN key via a modulo 97:

Example: The bank number is: 12345 12345 0123456789AZ 96

Step 1: Remove the key BBAN code.

Example: The key is composed of the last 2 digits: 96. The rest of the calculation is done with 12345 12345 0123456789AZ.

The checksum key is therefore 96 (the key removed previously), the BBAN is valid.

To make this modulo calculation, use a calculator that accepts calculation with large numbers (arbitrary precision) as proposed on dCode.

Why the modulo 97?

Why 97? Because it is a prime number (the largest with 2 digits) that will allow to minimize the errors.

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Source code

dCode retains ownership of the source code of the script BBAN Number online. Except explicit open source licence (indicated Creative Commons / free), any algorithm, applet, snippet, software (converter, solver, encryption / decryption, encoding / decoding, ciphering / deciphering, translator), or any function (convert, solve, decrypt, encrypt, decipher, cipher, decode, code, translate) written in any informatic langauge (PHP, Java, C#, Python, Javascript, Matlab, etc.) which dCode owns rights will not be given for free. So if you need to download the online BBAN Number script for offline use, check contact page !