IBAN stands for International Bank Account Number. It is a standardized format used in most of Europe and the Middle East that encodes the country, check digits, bank, and account number in a single string of up to 34 characters.

How is an IBAN validated?

An IBAN must start with a 2-letter country code and 2 check digits, match the expected length for its country, and pass the mod-97 check: when the first 4 characters are moved to the end, letters are converted to numbers (A=10..Z=35), and the result is divided by 97, the remainder must equal 1.

What is a SWIFT or BIC code?

A SWIFT/BIC (Bank Identifier Code) is 8 or 11 characters and identifies a specific bank for international wires. The structure is 4-letter bank code + 2-letter country code + 2-character location code + optional 3-character branch code (XXX or omitted means the primary office).

What is a US routing number?

A US ABA routing number is a 9-digit code that identifies a bank or credit union for ACH and wire transfers. It has a built-in checksum: 3×(d1+d4+d7) + 7×(d2+d5+d8) + (d3+d6+d9) must be divisible by 10.

Does this tool confirm the account exists or who owns it?

No. The Bank Account Number Checker only validates formatting and structure. It does not contact any bank, look up account holders, check balances, or confirm that an account exists. Always verify payment details directly with the recipient before sending money.

Are my inputs uploaded anywhere?

No. Every check runs entirely in your browser. Account numbers, IBANs, and SWIFT codes never leave your device.

Can the BBAN portion be alphanumeric?

Yes, in some countries (e.g. UK, Malta) the BBAN includes letters representing the sort code or branch identifier.

Understanding IBAN Numbers

The structure of an IBAN

Every IBAN starts with a 2-letter ISO country code, followed by 2 check digits, then the Basic Bank Account Number (BBAN) — the bank's own account identifier. Total length is fixed per country, from 15 characters in Norway to 34 in some Caribbean nations.

Country-specific lengths

The length is part of the spec. A 'GB' IBAN must be exactly 22 characters; a 'DE' IBAN must be 22 as well; a 'FR' IBAN is 27. Wrong length means wrong country code or a typo — there is no flexibility.

The mod-97 check

Move the first four characters to the end, convert each letter to two digits (A=10..Z=35), and divide the resulting number by 97. The remainder must equal 1. This catches almost every single-digit typo and most two-digit swaps.

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Bank Account Number Checker

Validate IBANs, SWIFT/BIC codes, US routing numbers, and country-specific bank account formats.

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Frequently asked questions

No. The United States, Canada, Australia, and several Asian countries don't use IBAN — they have their own national formats and rely on SWIFT/BIC for international wires.

Jun 3, 20265 min read