IBAN Validator
Validate IBAN numbers, check the country, length, and mod-97 checksum. Format, mask, and explain IBAN structure.
Mod-97 check — step by step
Type an IBAN to see the rearranged string, letter-to-number conversion, and final mod-97 result.
About this tool
Enter any International Bank Account Number (IBAN) and the tool verifies the ISO 13616 mod-97 checksum, identifies the country, and confirms the structure matches the expected length and format for that country. It also formats the IBAN into the standard 4-character groups and shows the rearranged string used in the mod-97 calculation so you can see exactly how the check works.
Example: GB82WEST12345698765432 passes the mod-97 check and is detected as a 22-character United Kingdom IBAN. DE89370400440532013000 is detected as a 22-character Germany IBAN.
Use the mask toggle to hide all but the last four characters when sharing a screen or taking screenshots. The tool works entirely in your browser; no IBAN is ever sent anywhere.
FAQ
Does this confirm that the bank account exists? ›
No. A valid IBAN means the number passes the mod-97 checksum and matches the country's expected length and format. It does not confirm the account exists, has funds, or is open. Only the receiving bank can confirm that, typically during a payment.
How is the mod-97 check calculated? ›
The two check digits and country code are moved from the front to the end of the IBAN, then every letter is converted to a number (A=10, B=11, … Z=35). The resulting large integer is divided by 97. If the remainder is 1, the IBAN is valid.
Why does my IBAN show as invalid? ›
The most common cause is a typo. The number must pass the mod-97 checksum and match the official length for its country. Check for missing or extra digits, transposed characters, or a wrong country code at the start.
What is the difference between an IBAN and a SWIFT/BIC code? ›
An IBAN identifies a specific bank account at a branch; a SWIFT/BIC code identifies the bank itself. For an international transfer you often need both: the SWIFT/BIC to route to the bank and the IBAN to credit the right account.