Gera Tools

Fake IBAN Generator (Test)

Valid-format IBAN numbers for testing bank flows

Produces structurally correct IBANs for multiple European countries using the right length, BBAN layout, and a real MOD-97 check-digit calculation. Intended for testing payment integrations in sandbox environments, not real transfers. It runs free in your browser on Gera Tools, with nothing uploaded.

Last updated Source: Gera Tools

Are these real bank accounts?

No. The bank and account portions are randomly generated, so the IBAN does not belong to any real account and cannot receive money. Only the structure and the MOD-97 check digits are correct, which is what format validators check.

A fake IBAN generator builds International Bank Account Numbers that are structurally correct and carry valid MOD-97 check digits, so they pass format validation in payment SDKs and sandbox environments. The bank and account digits are random, meaning the IBAN belongs to no real account and can never move money.

How it works

The generator follows the ISO 13616 IBAN standard for each country:

  1. The country code (two letters) and the registered total length are fixed per country.
  2. A BBAN (the country-specific bank and account part) is filled with random digits to the correct length.
  3. The check digits are computed: take BBAN + countryCode + "00", replace each letter with two digits (A=10 … Z=35), read the result as one large integer, compute it modulo 97, and set the check digits to 98 - (mod result).
  4. The final IBAN is countryCode + checkDigits + BBAN. Validating it (moving the first four characters to the end and taking mod 97) always yields 1.

Country lengths at a glance

CountryCodeLengthExample structure
GermanyDE22DE + 2 check + 18 BBAN
FranceFR27FR + 2 check + 23 BBAN
United KingdomGB22GB + 2 check + 18 BBAN
SpainES24ES + 2 check + 20 BBAN
NetherlandsNL18NL + 2 check + 14 BBAN

These lengths are registered with SWIFT and standardised under ISO 13616. Using the wrong length is one of the most common mistakes when writing manual IBAN test fixtures.

Worked example

For a German IBAN (DE, 22 characters total), the tool generates an 18-digit BBAN such as 500105170648489890. It then:

  1. Appends the country code and placeholder check digits: 500105170648489890DE00
  2. Converts letters to digits: D=13, E=14, giving 500105170648489890131400
  3. Computes 500105170648489890131400 mod 97 = 37
  4. Sets the check digits to 98 - 37 = 61
  5. Returns DE61500105170648489890

Paste that into any IBAN validator and it reports a valid checksum, because the same mod-97 step on the rearranged full string yields exactly 1.

What IBAN validation actually checks

Most client-side and API validators run two steps: first, confirm the total length matches the registered length for the country code; second, run the MOD-97 algorithm and verify the result is 1. These generated IBANs pass both. They will not pass a third type of check — real-time bank-account existence queries — because no account was ever opened with the generated BBAN. Use these IBANs for format-validation, storage, display, and payment-flow UI tests; use your sandbox account’s own IBAN for end-to-end payment submission tests.

Tips and notes

These are test fixtures only. Use them to verify formatting, storage, and validation paths — never to initiate a real transfer, which would fail at the bank. Generate a batch across several countries to check that your payment form handles different total lengths and localization patterns such as grouping spaces.