IBAN calculator
Runs in your browser. What you type is not sent or stored.
Your bank’s statement is the binding source of your IBAN. Calculated from the SWIFT IBAN Registry, updated September 17, 2026. Not a service of any bank. · Disclaimer
Choose the country, enter the bank code and the account number. The IBAN appears as you type, with the check digits worked out.
How to calculate an IBAN
- Pick the country of the account. The form switches to the words that country’s banks use: sort code, BLZ, ABI and CAB, entidad and oficina, code banque and code guichet.
- Type the bank code and the account number exactly as they appear on a cheque, card or statement. Leading zeros may be left out; we add them.
- Read the IBAN in groups of four and copy it with the button.
- Compare it once with the IBAN on your statement or in your banking app before you give it to anyone.
How the check digits are worked out
The two digits after the country code are not chosen by the bank. They are calculated: put the national number first, then the country code and 00, turn letters into numbers (A = 10 … Z = 35), divide by 97 and take 98 minus the remainder.
For the British example (sort code 12-34-56, account 98765432, bank code WEST) the result is 82, so the IBAN is GB82 WEST 1234 5698 7654 32. Every IBAN the calculator produces passes the IBAN checker.
Countries with their own form
For these countries the form asks for the local details and fills in the national check characters itself:
- United Kingdom and Ireland: bank code (4 letters), sort code, 8-digit account number.
- Germany: BLZ and account number; the bank name and BIC come from the Bundesbank list.
- Italy and San Marino: ABI, CAB and conto; the CIN letter is calculated.
- Spain: entidad, oficina and cuenta; the two DC digits are calculated.
- France and Monaco: code banque, code guichet and compte; the clé RIB is calculated.
- Austria, Switzerland, Liechtenstein, Belgium, Netherlands, Poland, Portugal: their national bank code and account number.
All other countries
Choose “Other countries” and type the national account number (BBAN) in the format shown. We calculate the two check digits. The national number has to be right already, because we cannot know your bank’s internal numbering.
When the calculator cannot be sure
Some banks convert old account numbers in their own way. In Germany these “IBAN rules” exist for a number of banks, and the Bundesbank publishes the list only to registered companies. So a German result is calculated by the standard rule and marked as such.
In the UK the four-letter bank code is not part of the sort code; you find it on your statement or in the bank’s BIC. When in doubt, the IBAN on your statement wins.
IBAN by country
| Country | Length | Example |
|---|---|---|
| Germany | 22 | DE89 3704 0044 0532 0130 00 |
| Austria | 20 | AT61 1904 3002 3457 3201 |
| Switzerland | 21 | CH93 0076 2011 6238 5295 7 |
| Italy | 27 | IT60 X054 2811 1010 0000 0123 456 |
| Spain | 24 | ES91 2100 0418 4502 0005 1332 |
| France | 27 | FR14 2004 1010 0505 0001 3M02 606 |
| Belgium | 16 | BE68 5390 0754 7034 |
| Netherlands | 18 | NL91 ABNA 0417 1643 00 |
| Poland | 28 | PL61 1090 1014 0000 0712 1981 2874 |
| Portugal | 25 | PT50 0002 0123 1234 5678 9015 4 |
| United Kingdom | 22 | GB29 NWBK 6016 1331 9268 19 |
| Ireland | 22 | IE29 AIBK 9311 5212 3456 78 |
Questions people ask
Can I work out my IBAN from my sort code and account number?
Yes, if you also know your bank’s 4-letter code (the first four letters of its BIC, such as NWBK or BARC). The rest is calculation.
Is a calculated IBAN as good as the one from my bank?
The arithmetic is exact. The risk is the input: a mistyped account number gives a well-formed IBAN for the wrong account. Always compare once with your statement.
Why does my German result carry a warning?
Some German banks use their own conversion rules, and which banks do is not public. The standard rule fits most accounts, but your bank’s IBAN is the binding one.
Do you store the account numbers I type?
No. The calculation runs in your browser. Nothing is sent or saved.