Technology calculators

IBAN Calculator

Updated Sep 1, 2026 By Jehan Wadia
Rate Formulas
IBAN Input
22 / 22 characters
Unknown digit? Use ? as a placeholder (e.g. DE12 5007 ?170 6484 89?0) and every valid completion will be listed.
Validation Result
Step-by-Step Solution

Introduction

An IBAN (International Bank Account Number) is the code you use to send and receive money across borders. One wrong letter or digit can send your payment to the wrong place, or make the bank reject it. This IBAN calculator helps you avoid that.

The tool has two tabs. Use Validate IBAN to check an IBAN you already have. Use Generate IBAN to build a new IBAN from a bank code, branch code, and account number. Both tabs work for more than 80 countries, from the UK and Germany to Brazil and Saudi Arabia.

Here is what you get with each check:

  • A clear valid or invalid answer, based on the official MOD-97-10 test.
  • A full step-by-step solution so you can see the math, not just the result.
  • A breakdown of every part of the IBAN: country code, check digits, bank code, branch code, and account number.
  • Bank and branch details, including the BIC/SWIFT code when it is in our directory.
  • SEPA info, so you know if the country supports SEPA transfers and direct debits.

Missing a digit? Type a question mark (?) in its place. The calculator will test every option and list each IBAN that passes the check. When you are done, you can copy the IBAN with one click or print the result for your records.

How to use our IBAN Calculator

Our IBAN calculator has two tabs. Use the first tab to check if an IBAN is valid. Use the second tab to build an IBAN from your bank details. Both tabs show the check digits, the bank and branch, the SEPA payment options, and the full math steps.

Validate IBAN tab

Enter IBAN: Type or paste the IBAN you want to check. Spaces are added for you, and the counter tells you how many characters that country needs.

Unknown characters (?): If a digit or letter is missing, type a question mark in its place. The tool tests every option and lists each IBAN that works.

Validate IBAN button: Click it to run the MOD-97-10 check. You get a valid or invalid result, the correct check digits, and a breakdown of each part of the IBAN.

Clear button: Click it to empty the field and start a new check.

Generate IBAN tab

Country: Pick the country of the bank account. This sets the IBAN length and shows which fields you must fill in.

Example buttons: Click UK, Germany, or France to load a working example and see how the tool fills each field.

Account fields: Fill in each box shown for your country, such as bank code, branch or sort code, and account number. Each box tells you how many characters it needs and whether it takes letters, digits, or both.

Calculate IBAN button: Click it to get your full IBAN with the correct check digits, in both print and electronic format. You can copy or print the result.

Clear button: Click it to reset the country and all fields.

What Is an IBAN?

An IBAN (International Bank Account Number) is a long code that points to one bank account anywhere in the world. Banks use it to send money to the right place, mostly for payments between countries. An IBAN does not replace your account number. It wraps your normal account details inside a standard format so foreign banks can read them.

The Parts of an IBAN

Every IBAN follows the same basic plan, set by the ISO 13616 standard:

  • Country code – 2 letters, like GB for the United Kingdom or DE for Germany.
  • Check digits – 2 numbers that prove the rest of the code was typed correctly.
  • BBAN – the Basic Bank Account Number. This holds the bank code, branch or sort code, and the account number.

Example: GB82 WEST 1234 5698 7654 32. Here GB is the country, 82 are the check digits, WEST is the bank code, 123456 is the sort code, and 98765432 is the account number.

IBAN Length by Country

The length is fixed for each country and never changes. Norway uses only 15 characters. The United Kingdom and Germany use 22. Malta uses 31, and Saint Lucia uses 32. If your IBAN is shorter or longer than your country's set length, it is wrong.

How the Check Digits Work

IBANs use a math test called MOD-97-10. It works like this:

  1. Move the first four characters (country code and check digits) to the end.
  2. Swap every letter for a number: A = 10, B = 11, all the way to Z = 35.
  3. Divide that huge number by 97.

If the leftover, or remainder, is 1, the IBAN passes. To build new check digits, you put "00" in their place, run the same math, then subtract the remainder from 98. This one test catches almost every typo, including swapped digits.

IBAN and SEPA

SEPA stands for the Single Euro Payments Area. It lets people in 36 countries send euros as easily as a local payment. SEPA services include Credit Transfer (SCT), Instant Credit Transfer (SCT Inst), and Direct Debit in Core and B2B versions. Not every IBAN country joins every SEPA scheme, so it helps to check before you set up a payment.

IBAN vs BIC

People often mix these up. The IBAN names the account. The BIC (also called a SWIFT code) names the bank itself, using 8 or 11 characters. Some transfers ask for both, though most SEPA payments now need only the IBAN.

Tips for Using an IBAN

  • Write it in groups of four characters on paper, but type it with no spaces online.
  • Always use capital letters.
  • Copy and paste when you can. Most failed payments come from one wrong character.
  • A passing check digit means the format is right. It does not prove the account is open or belongs to the person you think.
  • The United States, Canada, and Australia do not use IBANs. They use routing, transit, or BSB numbers instead.

Formulas used

Letter-to-digit conversion (A=10 … Z=35)
\text{value}(c) = \begin{cases} c & \text{if } c \in \{0,\dots,9\} \\ \operatorname{ASCII}(c) - 55 & \text{if } c \in \{A,\dots,Z\} \end{cases}
Rearrangement of the IBAN for validation
N = \operatorname{toDigits}(\text{BBAN} \Vert \text{CC} \Vert \text{check digits})
IBAN validity test (MOD-97-10)
N \bmod 97 = 1
Check digit calculation
\text{check} = 98 - \left( \operatorname{toDigits}(\text{BBAN} \Vert \text{CC} \Vert \texttt{00}) \bmod 97 \right)
Iterative modulo 97 over the digit string
r_0 = 0, \qquad r_i = (10 \cdot r_{i-1} + d_i) \bmod 97
Total IBAN length
L_{\text{IBAN}} = 2 + 2 + \sum_{i=1}^{k} \ell_i = 4 + L_{\text{BBAN}}
Number of wildcard completion candidates
T = \prod_{i=1}^{m} |S_i|

Frequently asked questions

Where do I find my IBAN?

Your IBAN is on your bank statement, usually near the top next to your account details. You can also see it in your banking app or online banking under account information. Some banks print it on the paperwork that came with your card.

If you cannot find it, ask your bank. Never guess or make one up from your account number.

Is it safe to give someone my IBAN?

Yes, if you want that person to pay you. An IBAN works like a mailing address for money. Anyone sending you funds needs it.

Still, treat it with care. Do not post it in public forums, and never share it along with your password, PIN, or card security code.

Can someone take money from my account with just my IBAN?

Not with a transfer. Money can only be pushed into your account, not pulled out with the IBAN alone.

The one exception is a direct debit, which needs your permission first. If an unapproved SEPA direct debit hits your account, you can normally ask your bank for a refund within 8 weeks.

What happens if I send money to the wrong IBAN?

If the IBAN fails the check digit test, the bank rejects the payment and your money stays put. That is the good case.

If the wrong IBAN still passes the test, the money goes to a real but different account. You must ask your bank to chase the other bank. The account holder has to agree to send it back, so there is no promise you get it. Check the IBAN before you press send.

Is an IBAN the same as a bank account number?

No. An IBAN holds your account number inside it, plus a country code, two check digits, and your bank or branch code.

For example, UK account 98765432 with sort code 12-34-56 becomes GB82 WEST 1234 5698 7654 32. Use your plain account number at home and the IBAN for payments from abroad.

Do I still need a SWIFT or BIC code if I have an IBAN?

For most payments inside the SEPA area, the IBAN alone is enough. Banks can work out the bank from the IBAN itself.

For payments to or from countries outside SEPA, many banks still ask for the BIC. Remember: the BIC names the bank, the IBAN names the account.

Why was my IBAN rejected even though it looks correct?

Common causes:

  • A letter O typed instead of the digit 0, or l instead of 1.
  • One missing or extra character, so the length is wrong for that country.
  • Old details after a bank merger or rebrand.
  • The account is closed, or it does not accept payments from abroad.
  • Lowercase letters or odd symbols pasted in from an email.

Check the length first, then the check digits.

Does my IBAN change if I move house?

No. Your address is not part of the IBAN, so moving home changes nothing.

Your IBAN does change if you switch to a new bank, close and reopen an account, or if your bank merges and issues new bank codes. When that happens, tell anyone who pays you.

How long does a payment to an IBAN take to arrive?

Inside SEPA, a normal credit transfer arrives by the next business day. SEPA Instant transfers land in about 10 seconds, day or night.

Payments to countries outside SEPA usually take 1 to 5 business days, because more banks handle the money along the way.

How many countries use IBAN?

More than 80 countries use IBAN today, and the list still grows. Nearly all of Europe uses it, plus much of the Middle East, North Africa, the Caribbean, and parts of South America.

Lengths differ by country, from 15 characters in Norway to 32 in Saint Lucia.

What is a virtual IBAN?

A virtual IBAN is an extra IBAN that points at one real bank account. It passes the same MOD-97-10 check as any other IBAN.

Businesses give each customer their own virtual IBAN so incoming payments are easy to match. The money still lands in the one main account behind them.

What is IBAN discrimination?

It is when a company refuses your IBAN because it starts with a different country code, such as rejecting a German IBAN for a French bill.

In the EU this is against the law under the SEPA Regulation. Any euro account in the SEPA area must be accepted for transfers and direct debits. You can report the company to your national authority.