Networking & Web

IBAN Validator

Check whether an IBAN is structurally valid using the official checksum algorithm, and see its country code and bank account number breakdown.

Free & unlimitedRuns in your browserNo sign-up required

IBAN number

✓ Valid IBAN

Country codeGB — United Kingdom

Check digits29

BBAN (bank-specific)NWBK60161331926819

FormattedGB29 NWBK 6016 1331 9268 19

Length22 characters

IBAN Validation Explained

IBAN (International Bank Account Number) is an internationally agreed standard for identifying bank accounts across national borders in financial transactions.

IBAN structure

An IBAN begins with a 2-letter ISO country code, followed by 2 numeric check digits, followed by the BBAN (Basic Bank Account Number) which is country-specific and can be up to 30 characters. The total length varies by country: UK IBANs are 22 characters, German are 22, French are 27.

How check digit validation works

To validate an IBAN: (1) Move the first 4 characters to the end. (2) Replace each letter with its numeric equivalent (A=10, B=11, ..., Z=35). (3) Compute the integer result modulo 97. If the remainder is 1, the IBAN is valid. This process detects all transposition and single-character errors.

IBAN vs. SWIFT/BIC

IBAN identifies the specific bank account. SWIFT/BIC (Bank Identifier Code) identifies the bank and branch. International transfers require both: the IBAN tells the destination account and the SWIFT/BIC code routes the payment to the correct financial institution.

Countries that use IBAN

All European Union member states mandate IBAN for SEPA transfers. Over 80 countries worldwide have adopted IBAN. The United States and Canada do not use IBAN — they use routing numbers + account numbers. Most Middle Eastern and Gulf Cooperation Council (GCC) countries have adopted IBAN.

Loading tool…

How it works

Three steps, no setup

Paste an IBAN

Spaces are stripped automatically before validation.

Run the checksum check

The ISO 7064 MOD-97-10 algorithm confirms whether the number is internally consistent.

Review the breakdown

Country, check digits, and the underlying BBAN are shown separately.

Common questions

Frequently asked questions

Does a valid checksum guarantee the account exists?

No — it only confirms the number is structurally well-formed. Verifying that the account is real still requires checking with the bank.

How many countries are supported?

IBAN structure rules for over 70 countries that use the standard are included.

Keep exploring

Related tools

View all tools

Networking & Web

IBAN Validator

IBAN Validation Explained

IBAN structure

How check digit validation works

IBAN vs. SWIFT/BIC

Countries that use IBAN

Three steps, no setup

Paste an IBAN

Run the checksum check

Review the breakdown

Frequently asked questions

Related tools

IPv4 Subnet Calculator

IPv4 Address Converter

IPv4 Range Expander

IPv6 ULA Generator

MAC Address Vendor Lookup

Random MAC Address Generator

twoworks

IBAN Validation Explained

IBAN structure

How check digit validation works

IBAN vs. SWIFT/BIC

Countries that use IBAN