Does a valid checksum mean the bank account is real?

No. The mod-97 checksum only confirms the IBAN's digits are internally consistent and weren't mistyped. Confirming the account actually exists and is open requires checking with the bank, not this tool.

Is my IBAN sent anywhere when I check it?

No, the checksum and parsing run with plain arithmetic in your browser tab, so the number you type, which is routing information rather than a password, stays on your device.

Why does it say the IBAN has the wrong length?

Each country has a fixed total IBAN length in the ISO registry this tool uses; if your input's country code is recognized but the character count doesn't match, that mismatch is reported before the checksum is even computed.

What is the BBAN part of the result?

BBAN stands for Basic Bank Account Number, the country-specific part of the IBAN after the two-letter country code and two check digits, typically encoding the bank code, branch and account number.

IBAN Validator & Parser

Validate an IBAN's checksum and break it into country, check digits and BBAN, locally.

Local, Runs entirely in your browser, your data never leaves your device.

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Check an IBAN's structure before you use it

This tool takes an International Bank Account Number, strips spaces, and runs the ISO 13616 mod-97 checksum against it, then splits the result into country code, check digits and BBAN. It's useful when you're keying in a supplier's bank details or debugging a payment file and want to catch a typo before it causes a failed SEPA transfer. Because an IBAN is bank routing information rather than a secret, checking it locally still means it never reaches a server you don't control.

How to use the IBAN Validator & Parser

Type or paste the IBAN into the input field, spaces are stripped automatically.
Read the status banner: green means the checksum and length both check out.
Review the Formatted, Country, Check digits and BBAN rows below the banner.
Compare Expected length against the actual value if the check fails on length.
Hover a row and click its copy icon to copy just that value.

A passing checksum only proves the IBAN is internally consistent, that its digits were typed or generated correctly. It does not confirm the account exists, belongs to a particular person, or is open at the bank; only the bank itself can verify that.

Expected lengths are tracked per country from the common IBAN registry, so an IBAN with a recognized country code but the wrong number of characters is flagged even before the checksum runs.

Frequently asked questions

Does a valid checksum mean the bank account is real?: No. The mod-97 checksum only confirms the IBAN's digits are internally consistent and weren't mistyped. Confirming the account actually exists and is open requires checking with the bank, not this tool.
Is my IBAN sent anywhere when I check it?: No, the checksum and parsing run with plain arithmetic in your browser tab, so the number you type, which is routing information rather than a password, stays on your device.
Why does it say the IBAN has the wrong length?: Each country has a fixed total IBAN length in the ISO registry this tool uses; if your input's country code is recognized but the character count doesn't match, that mismatch is reported before the checksum is even computed.
What is the BBAN part of the result?: BBAN stands for Basic Bank Account Number, the country-specific part of the IBAN after the two-letter country code and two check digits, typically encoding the bank code, branch and account number.