IBANs for all 27, checked twice

Every country's exact ISO 13616 format, correct mod-97 check digits — and, where the national account number embeds its own internal check digit, that one computed the real way too.

Belgium's mod-97 suffix, France's clé RIB, Italy's CIN, Spain's DC, Finland's Luhn, Estonia's 7-3-1, Croatia's per-field MOD 11-10. The outer checksum is the easy half; strict per-country validators check the inner one, and that's where generated IBANs usually fall over.

Bank identifiers come from a real registry per country, so you can pin the issuing bank.