IBAN generator: build an IBAN from country and BBAN or bank/branch/account, computing check digits

IBAN generator: construct an IBAN from a country code and the domestic account parts, computing the ISO 7064 mod-97-10 check digits. Takes a single BBAN string or named parts (bank code, branch code, account number); digit fields are left-padded with zeros to the country's registered widths. Returns the IBAN in electronic and print formats with its bank, branch and account parts. Covers the 89 SWIFT registry countries. Named parts work only where they span the whole BBAN; else pass the BBAN.

Output (data): iban (electronic format, no spaces), iban_print (grouped in fours), country, check_digits, bban, parts ({bank, branch, account} as parsed by the registry layout, each string|null: null where the country's registry layout defines no such field, e.g. branch for most countries and all three for HN), length, valid (always true on success: a built IBAN is valid by construction). Named parts are accepted only for countries where bank, branch and account together cover the whole BBAN (56 of 89); for the others (e.g. FR, ES, IT, BE with national check digits) pass bban. Digit fields shorter than their width are left-padded with zeros; letter fields must be exact.

Deterministic: identical input returns identical output, so the response is served with Cache-Control: private, max-age=31536000, immutable (the paying client may cache it indefinitely; shared caches must not, because the response is paid).

Sources: iban-registry ibantools 4.5.4, field layout schwifty 2026.7.3 (published 2026-04-10, MIT). Echoed in meta.sources.

Price: $0.05 USDC per call (x402, Base). Route contract version 1.0.0. Docs: https://api.duoleads.com/docs#id-iban-build