Check the account before the money leaves
A wrong IBAN is one of the few payment mistakes that is genuinely hard to undo. Once money lands in the wrong valid account it can be gone for good, and criminals know it: the fastest-growing payment fraud is not a hacked card but a fake invoice or a "we have changed our bank details" email that quietly swaps one IBAN for another. This free checker is the thirty-second habit that catches the honest typos and gives you the moment of pause the scams rely on you skipping. Paste an IBAN and it confirms the country, the length and the check digits, then breaks out the bank and account parts. It all runs in your browser.
How it works
- Paste the IBAN from the invoice, email or form, with or without spaces.
- See the three checks: a recognised country code, the exact length that country uses, and check digits that match the built-in checksum.
- Read the breakdown: the country, and where the structure is known, the bank code, branch and account number embedded in the number.
What the check digits actually prove
The two digits right after the country code are not part of the account. They are a checksum, a mod-97 calculation over every other character in the IBAN, defined by the ISO 13616 standard. Because they are derived from the whole number, changing a single digit, or transposing two, almost always breaks the checksum. That is why a validator can tell you an IBAN is mistyped without ever contacting a bank: the number is either internally consistent or it is not. A failed checksum means stop, re-read, and confirm before you pay.
Valid is not the same as safe
This is the point most IBAN tools miss, and the reason this one lives in a scam-checking suite. A valid IBAN only proves the number is well formed and could belong to a real account. It does not prove the account belongs to the person or company you think you are paying. Invoice-redirection fraud works entirely with valid IBANs, because the fraudster simply gives you the real, correctly formed number of their own account. No checksum can catch that. The only defence is to confirm any new or changed bank details directly with the payee, using a phone number or contact you already trust, and never the details printed on the suspicious invoice or email itself.
Why a dedicated tool beats a chatbot
Verifying an IBAN by hand means knowing the exact length for each of eighty-odd countries and running a mod-97 calculation across letters mapped to numbers. A general chatbot will attempt the arithmetic and often get it wrong, and pasting bank account numbers into one is exactly the kind of sensitive data you should keep off a third-party server. This checker uses a fixed country table and the standard formula, so the result is deterministic and repeatable, and the number never leaves your device. It covers the whole IBAN registry, including the UAE, Saudi Arabia, Qatar and the rest of the Gulf as well as the UK and all of Europe.
One check in a bigger habit
A valid IBAN is necessary but never sufficient. Use it alongside the rest of RealCheck: confirm the email that carried the invoice is not spoofed, that the link you were sent is not a lookalike domain, and that the sender is who they claim to be. The strongest protection against payment fraud is boring and reliable: slow down on any request to send money to new details, verify through a channel you chose, and treat urgency as a warning sign rather than a reason to hurry. This tool is a validator and an educational aid, not banking or legal advice, and it runs entirely in your browser.