IBAN validator
Paste an IBAN with or without spaces. The validator checks the characters, the length for its country and the mod 97 check digits, then shows the IBAN in groups of four with its country, check digits and the domestic account part (BBAN). Nothing is sent anywhere.
Runs in your browser: nothing you enter is sent anywhere.
How to use it
- Paste or type the IBAN. Spaces, hyphens and a leading “IBAN” are ignored, and lowercase letters are accepted.
- Read the result: valid, or the reason it is not.
- Copy the IBAN in groups of four, or the BBAN.
How it works
- The first two letters are the country code. The IBAN must have that country’s length (for example 22 for Germany and the United Kingdom, 27 for France).
- The next two digits are check digits.
- For the check, the first four characters move to the end, letters become numbers (A = 10, B = 11 … Z = 35), and the long number is divided by 97. The remainder must be 1.
Worked example
GB82 WEST 1234 5698 7654 32 becomes WEST12345698765432GB82, then 3214282912345698765432161182 (W = 32, E = 14, S = 28, T = 29, G = 16, B = 11). That number mod 97 is 1, so the IBAN is valid: country GB, check digits 82, BBAN WEST12345698765432.
Changing the 82 to 83 makes the check fail, and the tool reports that the check digits should be 82.
Tips
- Write IBANs in groups of four on paper and on screen; that is the standard print format.
- In electronic payment files IBANs are usually written without spaces.
- Some countries add their own national check digits inside the BBAN; this tool checks only the IBAN-wide mod 97 rule.
Frequently asked questions
How is an IBAN checked?
Move the first four characters to the end, replace each letter with a number (A = 10 … Z = 35) and divide the resulting number by 97. A valid IBAN leaves a remainder of 1. The length must also match the country.
Does a valid IBAN mean the account exists?
No. The check catches typing mistakes such as a wrong or swapped digit, but only the bank can confirm that an account exists and who owns it.
What is the BBAN?
The Basic Bank Account Number: everything after the country code and the check digits. It holds the bank code and the account number in a format set by each country.
What do the suggested check digits mean?
When the checksum fails, the tool works out the check digits that would make the rest of the IBAN valid. If the rest is right, those are the correct digits; if the mistake is elsewhere, the suggestion is wrong too.
Is my IBAN sent anywhere?
No. The check runs entirely in your browser.