How does the IBAN calculator work?

It puts the national details in the order the country’s IBAN format sets, then computes the two check digits with ISO 7064 (mod 97): the country code and 00 go to the end, letters become numbers, and 98 minus the remainder after dividing by 97 gives the check digits.

Why can’t I calculate an IBAN for every country?

Some countries put a national check digit inside the account number, computed with a method specific to their banks. Where we have not verified that method against the official example, we leave the country out rather than guess. That applies to 5 countries, listed below.

Is a calculated IBAN guaranteed to be right?

It is guaranteed to be well-formed. Whether it points at the right account depends on the details you typed, so ask the account holder or their bank to confirm it before a first payment.

What is the RIB key, and why don’t I type it?

In France, Monaco, Morocco, Tunisia and a few other countries the last two digits of the national number are a key computed from the bank, branch and account. The calculator works it out and shows it, so you can compare it with the key on the bank details: if they differ, a number was mistyped.

Free tool

IBAN calculator

Build an IBAN from a bank code, branch and account number, with the check digits worked out for you. 85 countries.

CountryBank code4 digitsBranch code4 digitsAccount number17 digits

Before you calculate an IBAN

01Use the numbers exactly as printed
Leading zeros count. The calculator never pads a field for you, because a short account number is usually a typo.
02National keys are computed
Where a country adds a national check digit (the French or Moroccan RIB key, Italy’s CIN, Spain’s control digits), it is worked out from the other fields and shown.
03Well-formed is not confirmed
A calculated IBAN always passes the checker. Only the account holder’s bank can confirm it is their account.
04Already have an IBAN?
Check it instead: the checker names the bank and tells you exactly what is wrong, if anything.

Open the IBAN checker

Countries the calculator covers

Each link opens the country’s IBAN format, with a worked example.

Countries left out, and why

These countries put a national check digit inside the account number, calculated with a method their banks use that we have not verified against the official example. Rather than guess, we leave them out: ask the bank for the IBAN, then check it with the IBAN checker.

Algeria does not use the IBAN at all: how to pay a RIB

IBAN calculator: questions

How does the IBAN calculator work?: It puts the national details in the order the country’s IBAN format sets, then computes the two check digits with ISO 7064 (mod 97): the country code and 00 go to the end, letters become numbers, and 98 minus the remainder after dividing by 97 gives the check digits.
Why can’t I calculate an IBAN for every country?: Some countries put a national check digit inside the account number, computed with a method specific to their banks. Where we have not verified that method against the official example, we leave the country out rather than guess. That applies to 5 countries, listed below.
Is a calculated IBAN guaranteed to be right?: It is guaranteed to be well-formed. Whether it points at the right account depends on the details you typed, so ask the account holder or their bank to confirm it before a first payment.
What is the RIB key, and why don’t I type it?: In France, Monaco, Morocco, Tunisia and a few other countries the last two digits of the national number are a key computed from the bank, branch and account. The calculator works it out and shows it, so you can compare it with the key on the bank details: if they differ, a number was mistyped.

Paying suppliers abroad, or getting paid in euro?

TrillioniPay gives a business its own euro IBAN, reachable by SEPA, and pays suppliers in 180+ countries. Accounts open first to the waiting list.

Join the waiting list Send money Get a euro IBAN