IBAN validator

Validate IBANs by checking country-specific length, format, and checksum.

IBAN

Enter an IBAN to format and validate it automatically.

Validation result

Review country support, expected length, checksum, BBAN, and normalized formats.

Enter an IBAN to see validation details.

What is an IBAN?

IBAN (International Bank Account Number) is a standardized identifier for bank accounts used in international payments.

IBAN structure

An IBAN starts with a two-letter country code, two check digits, and a country-specific BBAN.

Checksum validation

IBAN validity is checked with the ISO 13616 mod-97 algorithm.

  1. Remove spaces and move the first four characters to the end
  2. Convert letters to numbers (A=10, B=11, ..., Z=35)
  3. Compute mod 97; a valid IBAN leaves a remainder of 1

Each country defines a fixed length and structure for the BBAN portion.

How to use

Enter or paste an IBAN to format it automatically and check the country rules, expected length, structure, and mod-97 checksum. Copy the normalized IBAN, formatted IBAN, or BBAN from the result when available.