IBAN Calculator

A wrong IBAN is a nuisance: at best the transfer bounces, at worst the money ends up somewhere. The IBAN calculator catches typos before they get expensive. You paste an IBAN and the tool checks in real time whether the country code is known, whether the length matches the country and whether the checksum passes the internationally standardised modulo-97 method.

If something is off, the calculator tells you exactly what: wrong format, unknown country code, wrong length or a checksum that does not add up. That is far more helpful than a bare "invalid", because you immediately know whether you made a typo or whether the IBAN is fundamentally wrong.

Conversely the tool builds the matching IBAN from a German bank code (BLZ) and account number. The account number is automatically padded to ten digits with zeros, the check digits are calculated correctly. For the BLZ the calculator pulls the bank name and BIC from a directory of around 3,500 German bank codes. Important: the IBAN is created purely mathematically - only the bank can confirm whether the account actually exists.

The IBAN breakdown splits every valid IBAN into its building blocks: country code, check digits, bank code, account number and, depending on the country, branch or national check digit. For German IBANs you see the bank and BIC directly. So you understand what the 22 characters actually mean instead of just blindly copying them.

The batch mode validates several IBANs at once. You paste a list, one per line, and get the result for each plus a summary of how many are valid and how many invalid. Handy when you want to double-check a recipient list or a payment run. A formats tab also lists the length and structure of the IBAN per country.

From a valid IBAN the tool generates an EPC Girocode, the QR code for SEPA transfers under the EPC069-12 standard. You can scan it with most German and European banking apps to import the recipient details without retyping. The entire tool runs client-side, without signup and without sensitive bank data ever leaving your device.