How an IBAN is built
Every IBAN starts with a two-letter country code and two check digits, followed by the national bank code and account number. The length is fixed per country:
| Country | Length | Example |
|---|---|---|
| Croatia | 21 | HR12 1001 0051 8630 0016 0 |
| Germany | 22 | DE89 3704 0044 0532 0130 00 |
| Austria | 20 | AT61 1904 3002 3457 3201 |
| United Kingdom | 22 | GB82 WEST 1234 5698 7654 32 |
What the check catches, and what it doesn't
The tool calculates the check digits using the international standard (ISO 13616, MOD 97) and checks the length for the country. That catches almost every typo: a wrong digit, two swapped digits, or a character too many or too few.
The check cannot tell you whether the account exists or who owns it. A mathematically valid IBAN can belong to a closed account or to someone else. For larger payments and new suppliers, always confirm the details from a trusted source, such as a signed contract, and never only from an email.
Verification of Payee in the EU
Since 9 October 2025, banks in the euro area compare the payee name with the account holder for euro transfers (Verification of Payee) and warn you if they don't match. It is a good protection against invoice fraud, but it only checks the name, and only at the moment you pay. Validate an IBAN earlier, when you put it on an invoice, a quote or your website.
Common IBAN mistakes
- The letter O instead of zero, or I instead of one, especially when copying from paper.
- An old national account number instead of the full IBAN.
- An IBAN copied from a PDF with invisible characters. The tool cleans them up.
- Two neighbouring digits swapped. The check digits always catch this.
Frequently asked questions
Is it safe to check an IBAN here?
Does "valid" mean the account exists?
Can I find the bank from an IBAN?
Is a BIC/SWIFT code still needed?
Updated: November 2026 · Supremio Digital, Zagreb
