UK · France · Spain · Free · No signup
IBAN checker and calculator
Check a UK, French or Spanish IBAN, or calculate one from complete domestic details. See the country, bank identifier and account fields, with a link to convert your bank statements.
A passing result checks the number’s structure and checksum. It does not prove that an account exists, is open, belongs to a person, or is safe to pay. UK sort-code/account modulus checks are not performed.
Which IBANs can I check?
This page supports three national formats. It does not validate IBANs from other countries. The country is detected from the IBAN prefix or assumed from one of the complete domestic formats below. For domestic details, confirm the account’s country with your bank first.
| Country | IBAN | Complete domestic input | Checks performed |
|---|---|---|---|
| UK / GB format | GB + 20 characters | 4 bank letters + 6 sort-code digits + 8 account digits | Structure and IBAN MOD-97 |
| France | FR + 25 characters | 23-character RIB, including its key | Structure, IBAN MOD-97 and RIB key |
| Spain | ES + 22 digits | 20-digit CCC, including both control digits | Structure, IBAN MOD-97 and CCC controls |
GB is the UK IBAN prefix, not UK. The GB format is also used for the Isle of Man, Jersey and Guernsey. The prefix alone does not identify which of these territories holds the account.
How to read a UK IBAN and find its sort code
SWIFT’s published example is GB29 NWBK 6016 1331 9268 19. It is a demonstration only; do not use it to make a payment. The groups of four help reading, but do not mark the boundaries of the account fields.
| Field | Value | Meaning |
|---|---|---|
| Country prefix | GB | UK IBAN format |
| IBAN check digits | 29 | International checksum |
| Bank identifier | NWBK | NatWest identifier |
| Sort code | 601613 | Domestic branch / routing code: 60-16-13 |
| Account number | 31926819 | Eight account digits |
How to calculate an IBAN from account details
- UK: enter the four-letter bank identifier, six-digit sort code and eight-digit account number together, for example NWBK 601613 31926819. A sort code and account number alone do not supply the bank identifier this calculator needs. Ask your bank for the complete IBAN or confirmed identifier.
- France: enter the five-digit bank code, five-digit branch code, eleven-character account number and two-digit RIB key. Keep letters and leading zeroes. Use this only for an account held in France; a Monégasque RIB can have the same domestic shape and is outside this tool’s scope. A complete demonstration RIB is 20041 01005 0500013M026 06.
- Spain: enter the four-digit bank code, four-digit branch code, two CCC control digits and ten-digit account number. A complete demonstration CCC is 2100 0418 45 0200051332.
The calculator first checks the format and any supported domestic control digits. It then appends the country code and 00 to the domestic part, converts letters using A = 10 through Z = 35, and calculates 98 minus the remainder modulo 97. Those two digits go after the country prefix. French RIB letters use a different mapping for the domestic key, which is checked separately.
For an existing IBAN, moving its first four characters to the end and applying the same letter conversion must leave a remainder of 1 modulo 97. This detects many typing errors; it cannot verify the owner or a bank’s account records.
Common errors and questions
Why does my IBAN fail the check?
Check for missing characters, lost leading zeroes, O instead of 0, or I instead of 1. Copy just the number, without labels such as “IBAN:”. If a domestic or IBAN checksum fails, copy the full details from the bank again. Do not change only the check digits to make a doubtful number pass.
Can I find the bank from an IBAN?
We match the bank identifier against a selected directory. It covers five UK identifiers and the supported codes in our French and Spanish tools. If a bank is not listed, its name is not guessed. A passing checksum does not confirm the bank/sort-code combination, branch address or BIC. See the original bank document for those details.
Can I calculate my IBAN from a BIC or bank name?
Not with this tool. The BIC identifies a banking entity; an IBAN identifies an account. Do not assume that the first four letters of a BIC are the right IBAN identifier for your account. Use the IBAN your bank provides whenever possible.
Does a valid IBAN prove who owns the account?
No. Mathematical checks do not confirm account ownership, account activity or document authenticity. Confirm new payment details with the recipient using a contact you already trust. This page does not provide a bank’s Confirmation of Payee service.
Can I check a US account or any other country?
No. US domestic accounts do not use the UK, French or Spanish formats supported here. This page also does not check other IBAN prefixes, even if they use the international MOD-97 checksum. Use the issuing bank’s details for an unsupported account.
From account details to statement transactions
An IBAN identifies an account; it does not contain transactions. If you need dates, descriptions, debits, credits and balances in a spreadsheet, use the bank statement PDF and convert it to Excel or CSV. The result links to an English bank guide when one is available, or to the English statement converter.
Country-specific help is also available in French for French accounts and Spanish for Spanish accounts.
Method and sources
Built and explained by ExtractoCSV. Reviewed . No live bank lookup or account-owner search is performed.
- SWIFT IBAN Registry, release 103, September 2026: country structures and the GB demonstration.
- NatWest: IBAN format and where to find your own details; RBS Bankline guide; Lloyds payment guide; HSBC payment details; Convera’s HBUK identifier record. Selected UK identifier references; not a complete directory.
- DGFiP: French RIB-to-IBAN method; CCC and IBAN controls, Annex 1. The French and Spanish guides list their bank-code sources.