IBAN Validator
What is IBAN Validator
This tool checks whether an International Bank Account Number (IBAN) is structurally valid. It confirms the country code matches the official IBAN length from the international registry and runs the MOD-97 checksum defined in ISO 13616, the same math banks use to catch a mistyped digit before a transfer is sent. It also groups the number into readable 4-character blocks. Everything runs locally in your browser; no account number is ever sent to a server.
How to use
- Type or paste the IBAN into the field.
- Watch the country, length and checksum update as you type.
- Check the pass or fail badges for length and the MOD-97 checksum.
- Copy the formatted IBAN once it reads as valid.
When to use it
Wiring money abroad and want to catch a typo before the bank rejects the transfer? Paste DE89 3704 0044 0532 0130 00 and you instantly see it's a valid German IBAN with a passing checksum, so if a real account number fails here, you know to double-check it with the sender before moving any money. Handy for accountants processing SEPA payments, developers validating a payment form, or anyone confirming a bank detail they got over the phone.
Frequently asked questions
Does this tool confirm the IBAN belongs to a real, open account?
No. It only confirms the number is mathematically well-formed, the country code is known and the length and MOD-97 checksum are correct. It can't tell you if the account exists, belongs to the person you think it does, or is still open, only the receiving bank can confirm that.
What is the MOD-97 checksum?
It's the check defined in ISO 13616: move the first four characters to the end, convert every letter to a two-digit number (A=10, B=11...Z=35), and the resulting number must leave a remainder of 1 when divided by 97. Nearly every typo or transposed digit breaks this check.
Why does the tool say the length is wrong even though the checksum passed?
Each country has one fixed IBAN length, for example 22 characters for Germany or 27 for France. A made-up number can pass the checksum by chance while still having the wrong length for its country, so the tool checks both independently.
Which countries does this tool recognize?
It covers every country in the official IBAN registry, from Andorra to Vatican City. If a country code isn't in that list, the tool still runs the MOD-97 checksum but can't confirm the expected length.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Copy link button, anyone who opens the link will see your exact inputs ready to go.
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