Free IBAN Validator

What is an IBAN?

An IBAN, or International Bank Account Number, is a standardised way to identify a bank account anywhere in the world. It was created by the European Committee for Banking Standards and is now used by 77 countries, mostly across Europe, the Middle East, and parts of the Caribbean and Central Asia. An IBAN wraps a bank's existing domestic account number in a consistent format so that banks in different countries can process international transfers without manual reformatting or guesswork.

IBAN format explained

Every IBAN starts with a 2-letter ISO country code, followed by 2 check digits, and then the Basic Bank Account Number (BBAN) — the domestic account details specific to that country. Length varies by country: a UK IBAN is 22 characters, a German IBAN is 22 characters, a Norwegian IBAN is just 15 characters (the shortest), and a Maltese IBAN is 31 characters (the longest). The BBAN itself typically includes a bank code, sometimes a branch code, and the underlying account number.

How Banqcheq validates your IBAN

Banqcheq checks three things in order. First, it confirms the country code is a recognised IBAN country and that the total length matches what that country requires — any GB IBAN that isn't exactly 22 characters is immediately flagged. Second, it runs the official ISO 7064 mod-97 checksum algorithm: the first four characters are moved to the end, letters are converted to numbers (A=10 through Z=35), and the resulting number must leave a remainder of exactly 1 when divided by 97. Third, where the bank code is recognised, it looks up the bank name so you can confirm you're sending money to the right institution.

Which countries use IBAN?

IBAN is mandatory across the entire SEPA zone (36 European countries) and is also used across most of the Middle East and Gulf states — including the UAE, Saudi Arabia, and Qatar — plus a handful of countries elsewhere such as Brazil and Pakistan. Notably, the US, Canada, Australia, and most of Asia do not use IBAN at all; they rely on routing numbers, sort codes, or local bank codes instead, which is why Banqcheq also validates ACH, IFSC, and SWIFT formats separately.

Common IBAN errors

The most frequent mistakes are: transposed digits when copying by hand, a missing or extra character that throws off the length check, using an old account number instead of the full IBAN format, and confusing an IBAN with a SWIFT/BIC code — they serve different purposes and are often required together for cross-border SWIFT payments. Running your IBAN through Banqcheq before sending a payment catches all of these instantly, for free.