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About Iban Validator Online
This tool validates International Bank Account Numbers (IBANs) for syntax and checksum compliance. Enter an IBAN — like "GB29 NWBK 6016 1331 9268 19" — and the tool checks the length (specific to each country), the country code, the bank/branch code structure, and the two-digit checksum.
IBAN validation catches typos before money is sent. Bank transfers use the IBAN as the destination address; a mistyped IBAN can route money to the wrong account, often unrecoverable. Validating client-side prevents these costly mistakes before submission.
The validator works for all SEPA countries plus most other countries that have adopted IBAN (over 70 in total). It checks structural validity only — not whether the account actually exists or is active.
How to use this tool
How to validate an IBAN's checksum
Enter the IBAN
Paste the IBAN into the "IBAN" field. Spaces are stripped and letters are uppercased, so `de89 3704 0044 0532 0130 00` parses identically to `DE89370400440532013000`.
Press Run
Result returns `length` (post-cleanup) and `checksumValid` (boolean). The mod-97 checksum (per ISO 13616): move first four chars to the end, replace letters A=10…Z=35, the resulting number mod 97 must equal 1.
What checksumValid doesn't prove
A valid checksum does NOT prove the account exists, that the bank code is currently active, or that the IBAN belongs to the named beneficiary. For SEPA payments your bank still validates further server-side.
Country length hints
DE is 22 chars, FR 27, IT 27, GB 22, NL 18, ES 24, SA 24, AE 23. Wrong length for the leading 2-letter country code is a strong typo signal even before checksum runs.