IBAN Validator & Generator
Validate an IBAN's MOD-97 checksum, or generate a test IBAN for any supported country
Generated IBANs pass the MOD-97 checksum and have the correct length for the selected country, but are randomly generated — they are not real, bank-issued account numbers. Use them for testing form validation and API integrations only.
About this tool
The IBAN Validator & Generator checks whether an International Bank Account Number is structurally valid using the same MOD-97-10 checksum algorithm (ISO 7064) that every real IBAN is built on, plus a per-country length check across 35+ IBAN-using countries. Paste any IBAN and instantly see whether it passes, along with its country, check digits, and BBAN broken out separately. The generator side produces random test IBANs that pass the real checksum for a chosen country — useful for populating a form, testing validation logic, or exercising a payment integration's IBAN field without needing a real bank account number. Generated IBANs are not tied to any real account; they're structurally valid but synthetic, the same approach used by other IBAN test-data generators. Everything runs client-side — no IBAN you paste in, real or generated, is transmitted anywhere.
When to use it
- →Validating an IBAN a user entered in a form before submitting it to a payment processor
- →Generating test IBANs for a specific country to exercise payment-form validation logic
- →Checking whether an IBAN's check digits are internally consistent before troubleshooting a failed transfer
- →Learning how the MOD-97 checksum in an IBAN actually works
Tips
- ◆A failed checksum almost always means a typo somewhere in the number — re-check digit-by-digit rather than assuming the whole IBAN is fabricated.
- ◆Generated test IBANs pass the checksum and have correct length, but are not real, bank-issued accounts — never use them for anything beyond testing your own form or integration logic.
- ◆The length check only runs for countries in the built-in list — an unrecognized country code skips that check but still validates the checksum.
Frequently asked questions
What does the MOD-97 checksum actually verify?
It confirms the IBAN's digits are internally self-consistent per the ISO 7064 MOD 97-10 algorithm — the same math every bank's IBAN validation uses. It does not confirm the account actually exists, is open, or belongs to any particular person; checksum validity and account existence are two completely different things.
Can I use a generated test IBAN to actually send or receive money?
No. A generated IBAN passes the structural checksum and length check, but it's randomly generated — it doesn't correspond to any real bank or account. It's meant purely for testing form validation and API integrations, not for any real transaction.
Why did a real IBAN I typed in fail validation?
The most common cause by far is a single mistyped or transposed digit — even one wrong character anywhere in the IBAN will fail the checksum. Double-check the number character by character against its source, paying particular attention to easily confused characters like 0/O and 1/I.