IBAN Validator
Verify that an IBAN (International Bank Account Number) is properly formatted and that its mod-97 checksum is valid, handy before saving a wire transfer recipient.
How it works
An IBAN starts with a 2-letter country code, followed by a 2-digit check key, then the national bank account number. The check key is calculated using the mod-97 algorithm defined by ISO 7064: this tool verifies that the general format is respected, then recalculates this key to confirm that the entered IBAN has not been altered by a typo.
Does this tool verify that the account actually exists?
No, the mod-97 check only confirms that the IBAN is structurally consistent (no typo in the numbers), not that the corresponding bank account exists or is active. Only your bank can confirm the actual existence of an account.
Why is my IBAN marked invalid when it looks correct?
The most common cause is an input error: a reversed digit, a missing character, or a misplaced space is enough to make the checksum fail. Copy the IBAN directly from an official document rather than retyping it from memory.
100% local processing: the check runs entirely in your browser via WebAssembly; your IBAN is never sent to a server.