IBAN Checker
Check that an IBAN has the right length for its country and valid check digits. Free, no sign-up: the check runs in your browser and nothing is sent.
An IBAN from any country, a French RIB or a five-digit French bank code. Spaces are ignored.
How an IBAN is checked
An IBAN is a two-letter country code, two check digits, then the domestic account number (the BBAN). Each country fixes the total length: 22 characters in Germany and the UK, 27 in France and Italy, 18 in the Netherlands.
The check digits are computed by the bank over the whole IBAN (ISO 13616, mod 97). They catch any single wrong character and almost every pair of swapped characters. French and Monaco IBANs carry a second, national key inside the account number, the RIB key, which the checker tests too.
What valid check digits do not tell you
They rule out a typo or a digit edited by hand in a PDF. They say nothing about who owns the account. In payment-diversion fraud, the fraudster does not alter your IBAN: they replace it with their own, which has valid check digits.
What catches that is the account holder, the IBAN compared with the rest of the file, and how the document was made. For bank details received as a PDF, the PDF metadata viewer shows which software produced or edited it.
Frequently asked questions
What does the checker verify?
For any IBAN: the length its country requires and its check digits (the two digits after the country code, mod 97). For French and Monaco accounts, also the national RIB key, and the bank behind the bank code.
Is the number I type sent anywhere?
No. The check runs in your browser: what you type is sent to no server, neither Holofin's nor anyone else's, and nothing is stored.
Why doesn't it show the correct check digits?
Because it is built to verify an account number you received, not to complete one. Wrong check digits mean at least one character was mistyped or changed after the bank issued it. The fix is to ask for the details again, not to recompute the digits.
Do valid check digits prove the account is genuine?
No. A fraudster who swaps in their own IBAN supplies one with valid check digits. The check catches a typo or a digit edited by hand; it says nothing about who owns the account. Verify the account holder too, and confirm any change of bank details through a channel you already know.
Which countries are covered?
Every country in the IBAN registry for the length and mod-97 check. National check digits and bank names are only read for French and Monaco IBANs, which share the French RIB layout.
Hundreds of files to check?
Holofin reads every document in a file, extracts the data and runs more than 100 fraud checks on it: bank details against the applicant, metadata, PDF structure, fonts, totals, and Holograin for documents redrawn by AI.
See fraud detection
