What is an IBAN?

An IBAN, or International Bank Account Number, is a standardized international system for identifying bank accounts across national borders. It was originally developed by the European Committee for Banking Standards (ECBS) to facilitate payments within the European Union, but it has now been adopted by most countries around the world. The primary purpose of an IBAN is to reduce the risk of transcription errors in international fund transfers. By containing all necessary routing information in a standardized format, it helps to ensure that payments are processed automatically and reach their intended recipient without delays or errors.

The Structure of an IBAN

An IBAN is not a new account number; it is an additional layer of information that is added to an existing domestic bank account number. While the length can vary from country to country (up to a maximum of 34 characters), the structure is always the same:

1. Country Code (2 letters): The first two letters identify the country where the account is held (e.g., GB for Great Britain, DE for Germany, FR for France).
2. Checksum Digits (2 numbers): These two digits are the key to the IBAN's validation system. They are calculated using a mathematical formula (MOD-97) based on all the other characters in the IBAN. This allows a system to quickly check if the IBAN was typed correctly.
3. Basic Bank Account Number (BBAN): This is the country-specific part of the IBAN. It contains the domestic bank account number, branch identifier, and other routing information. The format and length of the BBAN vary for each country.

How IBAN Validation Works: The MOD-97 Check

The magic behind an IBAN validator is the MOD-97 algorithm. It's a simple but powerful way to check the integrity of the entire number. Here's how it works:

1. Move the first four characters of the IBAN (the country code and checksum) to the end.
2. Replace all letters in the string with numbers, where A=10, B=11, ..., Z=35.
3. Treat the resulting long number as an integer and calculate its remainder when divided by 97 (this is the "modulo 97" operation).

If the IBAN is valid, the remainder will always be 1. Our calculator performs this check instantly to tell you if the IBAN is mathematically correct.

Why Validation is Crucial

Validating an IBAN before initiating a transfer is a critical step that can save you time, money, and stress.

• Preventing Failed Payments: A single typo in a long account number can cause a payment to be rejected. The receiving bank will return the funds, but this can take days or even weeks, and you may be charged fees by both your bank and the receiving bank.
• Avoiding Delays: A correct IBAN allows for Straight-Through Processing (STP), where payments are handled automatically without manual intervention, ensuring they are processed quickly.
• Reducing Costs: Failed or delayed payments often incur significant bank charges. Validating the IBAN beforehand is a simple, free way to avoid these unnecessary costs.

IBAN vs. SWIFT/BIC

It's important not to confuse an IBAN with a SWIFT code (also known as a BIC, or Bank Identifier Code).

• An IBAN identifies an individual bank account.
• A SWIFT/BIC code identifies a specific bank or financial institution in the global network.

For most international transfers, you will need to provide both the recipient's IBAN and their bank's SWIFT/BIC code.

Frequently Asked Questions (FAQs)

1. How do I use the IBAN Validator?

Simply type or paste the IBAN you want to check into the input field. The calculator will instantly perform the validation checks and show you the result.

2. Does a "Valid" result guarantee the account exists?

No. This tool validates that the IBAN's format, length, and checksum are mathematically correct according to the standards for its country. It confirms the IBAN *could* exist, but it does not check against any bank's database to confirm that the account *actually* exists or belongs to the intended recipient. This validation is the first and most important step to prevent typing errors.

3. Which countries use IBAN?

Most countries in Europe, the Middle East, and the Caribbean use the IBAN system. Major economies like the United States, Canada, Australia, and China do not currently use IBAN for their domestic accounts, relying on other systems instead.