IBAN Validator & Generator

What this tool does

An IBAN isn't just a long string of characters — the last two digits of the country prefix are a checksum computed from everything else, using the MOD-97 algorithm defined in ISO 13616. That means most typos (swapped digits, a dropped character, a wrong check digit) can be caught instantly without ever contacting a bank. This tool runs that exact validation: it checks the country code is recognized, confirms the IBAN's length matches what that country requires, and verifies the MOD-97 checksum passes. It also works the other way — pick a country and generate a random, structurally valid test IBAN for form testing, QA, or sample data, complete with correctly computed check digits.

How to use it

• Paste or type an IBAN into the validator field — spacing and case don't matter, it's normalized automatically.
• Results update live: a formatted, grouped-by-4 display, the country, check digits, BBAN (the rest of the account identifier), and whether the length and checksum both pass.
• To generate a test IBAN instead, pick a country from the dropdown (all countries with a defined IBAN length are listed) and click Generate.
• Copy the generated IBAN, or click "Validate This" to immediately run it back through the validator above and see the same breakdown.

Real-world uses

Building or testing a payment form that accepts IBANs and want to catch obvious typos client-side before a user submits, or before you hit a payment API that charges per validation call? Run the format and checksum check here first. Need realistic-looking but clearly fake IBANs to populate a staging database, a demo, or automated test suite without using anyone's real account details? Generate as many as you need per country. Double-checking an IBAN a client or vendor sent you before wiring money, to catch a transposed digit before it becomes a failed (or worse, misdirected) transfer? A quick paste here confirms it's at least structurally sound.

Frequently asked questions

Does a valid checksum mean the bank account actually exists?

No. The MOD-97 checksum only confirms the IBAN is internally consistent and free of common typos — it says nothing about whether that specific account exists, is open, or belongs to whoever claims it. Only the account-holding bank can confirm that.

What is the MOD-97 algorithm?

It's the checksum method defined in ISO 7064 and used by ISO 13616 (the IBAN standard). The first four characters are moved to the end, every letter is converted to a two-digit number (A=10 through Z=35), and the resulting numeric string is checked for a remainder of exactly 1 when divided by 97.

Are the generated IBANs real bank accounts?

No — the account-specific digits are randomly generated, so a generated IBAN is not linked to any real account. It only satisfies the same length and checksum rules a real IBAN would, which makes it useful for testing input validation without using anyone's actual banking details.

Why did a real IBAN fail validation here?

Double-check for a mistyped character, a missing digit, or extra whitespace copied along with it. If the checksum still fails after cleaning it up, it's worth re-copying the IBAN directly from its original source, since even one wrong character will fail the MOD-97 check.

Is my IBAN data sent anywhere?

No — every calculation, both validating and generating, runs entirely in your browser using JavaScript. Nothing is transmitted to a server or stored.