About IBAN Works

IBAN Works is a free IBAN checker that tells you exactly what it checked and what it found. It runs entirely in your browser.

Why it exists

Most IBAN checkers give you a green tick or a red cross. That is not much help when you are about to send money, or when you are cleaning up a supplier file and need to know which entries are wrong and why.

IBAN Works reports every check separately: the country, the length, the pattern of letters and digits, and the check digits. When something fails, it tells you which character or which rule.

What it checks today

• Country: the first two letters must be a country that uses IBANs.
• Length: every country has one fixed length.
• Structure: each position must be a digit or a letter, as set out in the IBAN Registry.
• Check digits: the two digits after the country code are recalculated with ISO 7064 MOD 97-10.

What is coming

National account checks are next. Many countries had their own check digits inside account numbers long before IBAN existed, and they catch errors that MOD-97 cannot. Germany, the UK, France, Spain, Italy and Belgium come first, followed by converters such as BLZ to IBAN and RIB to IBAN.

Your data

The checker runs in your browser. Our code never sends what you type to a server. The privacy policy has the details.