IBAN Generator
Generate mod-97 valid test IBANs for development and testing. Not real accounts.
How this tool works
An IBAN cannot be generated without the underlying national account number, because the check digits are a function of the country code and the national part. What can be produced is a correctly formatted IBAN with the check digits computed for whatever national part you supply, and that is what this tool does.
The useful cases are testing and reconciliation: generating a valid-format IBAN for a country when you have the BBAN, producing a set of plausible-looking test IBANs for a locale, or checking how a downstream system handles a particular country format. The result is a well-formed identifier, and it should only be used against test data.
Worked example
| Step | Value |
|---|---|
| Country | GB |
| BBAN supplied | WEST12345698765432 |
| Country code and zeros | GB00WEST12345698765432 |
| Mod 97-10 | 82 |
| Result | GB82 WEST 1234 5698 7654 32 |
The check digits are derived, so the output is always structurally valid. It does not identify a real account.
When to use it
- Generate a valid-format IBAN for a test suite
- Test how a payment integration handles a particular country format
- Produce a set of test identifiers in a given country format
- Check the mod 97-10 implementation in your own code
Frequently asked questions
Can you generate a real IBAN?
No, and the tool does not try. The check digits are computed from the national account number you supply, which produces a structurally valid identifier. It does not correspond to a real account, and it must not be used for anything but testing.
What do I need to generate an IBAN?
The country code and the national account number, the BBAN, for that country. The check digits are then computed.
What is a BBAN?
The Basic Bank Account Number: the national part of an IBAN, which is the account number with whatever domestic structure the country uses, and which varies in length and alphabet between countries.
Is a generated IBAN guaranteed to pass validation?
Yes, if the national part is of the correct length and alphabet for the country. It is guaranteed to pass the checksum, and to be no more than that.
Why do different countries have different IBAN lengths?
Because the national account number is what varies. Germany uses 18 BBAN characters, France 23, and the UK 18, and the IBAN is the country code and check digits plus whatever the country uses.