IBAN checker.
Paste your IBAN, or a client’s or supplier’s. We tell you whether its check digits match and, for a Spanish account, which bank it is with and what each part means.
Check result
Valid IBAN: the check digits match.
In groups of four
ES91 2100 0418 4502 0005 1332
- ES91Country and check
- 2100Bank
- 0418Branch
- 45Account check
- 0200051332Account number
- Country
- Spain (ES)
- Length
- 24 of 24
- Bank
- CaixaBank
An estimate under 2026 rules. Your case may have details that change it, so check before you decide. Calculated in your browser: nothing you type is sent or stored.
How it is calculated.
We clean the IBAN.
Spaces and hyphens go. An IBAN starts with the two letters of the country and two check digits.
We check its length.
Each country has its own in Swift’s IBAN Registry (ISO 13616): 24 characters in Spain, 22 in Germany and 27 in France.
The mod-97 test.
The first four characters move to the end, each letter becomes a number (A = 10 … Z = 35) and the result is divided by 97. A remainder of 1 means the IBAN is right.
The parts of a Spanish IBAN.
After ES and the check digits come 4 digits for the bank (its Banco de España code), 4 for the branch, 2 account check digits and the 10-digit account number.
Would you rather Melso did it?
Your agent gathers invoices and expenses on WhatsApp, and your advisors prepare and file your taxes after you approve them in the app.
What people ask us most.
From its check digits: the whole IBAN, with letters turned into numbers, must leave a remainder of 1 when divided by 97. Mistyping one character or swapping two almost always breaks that.
24 characters: ES, two check digits, 4 for the bank, 4 for the branch, 2 account check digits and the 10-digit account number. It is usually written in groups of four, like ES91 2100 0418 4502 0005 1332.
Not necessarily. The checker confirms it is written correctly, not that the account is still open or who holds it. Before a direct debit or a large transfer, confirm it with the account holder.
In a Spanish IBAN, the four digits after the check digits are the bank’s code, given by the Banco de España, Spain’s central bank. We show the name of the largest banks; you can look up the rest in its register of institutions.
Leave the maths to your tax advisor.
Tell us about your situation. We confirm the scope before work starts.