IBAN Validator & Formatter — Check an International Bank Account Number (free, no upload)
Validate any IBAN with the ISO 13616 mod-97 checksum and country length rules, see which country it belongs to, and format it in groups of four. No upload.
🔒 Validated in your browser — nothing is uploaded.
Free IBAN validator & formatter — nothing uploaded
An IBAN (International Bank Account Number) validator checks whether a bank account number is well-formed before you rely on it for a payment. Paste an IBAN and this tool tells you live whether it is valid, which country it belongs to, and the tidy grouped format banks print on statements. Every check runs in your browser — no account, no upload.
How an IBAN is validated
Validation follows the ISO 13616 standard in three steps. First, the structure must be a two-letter country code, two check digits, then the country's account portion. Second, the total length must match that country's fixed IBAN length — Germany is 22, the United Kingdom 22, France 27, and so on. Third, the mod-97 checksum from ISO 7064 must pass: the first four characters move to the end, letters become numbers (A=10 up to Z=35), and the resulting integer must leave a remainder of 1 when divided by 97. A single mistyped digit almost always breaks this checksum, which is exactly what it is designed to catch.
What a valid result means (and what it does not)
A valid IBAN is correctly structured and passes the checksum, so it is safe from typos and transcription slips. It does not confirm that the account actually exists or that the holder name matches — only the receiving bank can confirm that. Think of it as spell-check for account numbers.
Format an IBAN into groups of four
Banks show IBANs in blocks of four characters, such as GB82 WEST 1234 5698 7654 32, to make them easier to read and re-key. This tool uppercases the value, strips stray spaces, and regroups it, so you can copy the clean version in one click.
Which countries use IBAN
IBAN is used across the EU and EEA and in many countries of the Middle East, the Balkans and beyond — over 80 in total. The validator recognises each registered country code and its required length. Some countries, including the United States, Canada, Australia and South Korea, do not use IBAN at all, so an account number from there will never validate as one.
Private by design
Bank details are sensitive, so nothing you type is sent anywhere — the IBAN never leaves your browser. That is why there is no sign-up.
Frequently asked questions
What does it mean when an IBAN is valid?
It means the IBAN has the correct structure for its country, the right length, and passes the mod-97 check digit test — so it is free of typos and transcription errors. It does not prove the account exists; only the bank can confirm that.
How does IBAN validation work?
It uses the ISO 13616 / ISO 7064 mod-97 algorithm. The first four characters are moved to the end, each letter is replaced by two digits (A=10 up to Z=35), and the resulting number is divided by 97. A valid IBAN leaves a remainder of exactly 1. The tool also checks that the length matches the country code.
Does a valid IBAN mean the bank account exists?
No. Validation catches typos and malformed numbers, but it cannot tell you whether the account is real, open, or belongs to a particular person. Only the receiving bank can verify that when a payment is made.
Why is my IBAN showing as invalid?
The most common causes are a mistyped or missing digit (which fails the checksum), the wrong number of characters for the country, an unsupported or misspelled country code, or extra characters pasted in by accident. The tool tells you which of these is the problem.
Is my IBAN uploaded anywhere?
No. The entire check runs locally in your browser with JavaScript. Your bank details never leave your device and nothing is sent to a server, which is why there is no sign-up.
Which countries use an IBAN?
Over 80 countries across the EU and EEA, plus much of the Middle East and the Balkans. Countries such as the United States, Canada, Australia and South Korea do not use IBAN, so their account numbers will not validate here.