About the IBAN Validator
An IBAN, the International Bank Account Number, identifies a bank account across borders. It starts with two letters for the country and two check digits, followed by the local account details. This tool checks the structure and the checksum: the country code, the length that this country uses and the mod-97 calculation. It does not check whether the account exists. Type an IBAN and the IBAN check appears at once, with a few related figures underneath, and you can copy the result with one tap. The sums run in your browser, so nothing you enter is uploaded.
Updated October 2026
How to use the IBAN Validator
- 1Enter an IBAN.
- 2Pick the units or options from the menus if the IBAN check tool offers them.
- 3Read the IBAN check in the large result box.
- 4Look at the extra rows for related figures.
- 5Press Copy result to keep the answer.
When you need the IBAN check
Finance teams, online shops and developers use IBAN checks to catch typing errors before a payment is sent. A failed check saves a returned transfer and the fees that come with it.
The tool formats the IBAN in groups of four, as it is usually printed. Spaces in your input are ignored and letters can be in any case.
How the IBAN check is worked out
Move the first four characters to the end, replace each letter by two digits (A = 10 … Z = 35), and the resulting number must leave a remainder of 1 when divided by 97. The documentation example GB82 WEST 1234 5698 7654 32 passes: the country GB uses 22 characters, and the checksum is correct. Changing the last digit makes the checksum fail. A German IBAN must have 22 characters, a Dutch one 18 and a French one 27.
Every answer on this page comes from that one rule, so you can check any result by hand with a calculator. The figures shown underneath, such as other units, are conversions of the same answer.
- Country length check
- Mod-97 checksum
- Formatted output
Mistakes to avoid with IBAN check
A valid IBAN is not proof that the account is open or that it belongs to the person you think. Always confirm payment details with the payee. About 75 countries are in the length table; for others only the checksum is tested, and the tool says so.
On phone and computer
On a phone, type into the boxes one after another and read the IBAN check underneath; Copy result puts it on the clipboard for a message or a note. On a computer the inputs sit on the left and the answer on the right, so you can change one figure and watch the IBAN check move. The iban validator works the same on both. Number checks come in different kinds. Use Luhn Validator for cards, Check Digit Calculator for codes, ISBN Converter for books, and Barcode Generator to print a code.
Features
- Valid does not mean open
- Confirm with the payee
- Spaces are ignored
- Clear messages when the IBAN check inputs make no sense
- Copy the result with one tap
- Private: nothing is uploaded
Frequently asked questions
How do I calculate IBAN check?
Move the first four characters to the end, replace each letter by two digits (A = 10 … Z = 35), and the resulting number must leave a remainder of 1 when divided by 97. The documentation example GB82 WEST 1234 5698 7654 32 passes: the country GB uses 22 characters, and the checksum is correct. Changing the last digit makes the checksum fail. A German IBAN must have 22 characters, a Dutch one 18 and a French one 27.
What is the formula for IBAN check?
Move the first four characters to the end, replace each letter by two digits (A = 10 … Z = 35), and the resulting number must leave a remainder of 1 when divided by 97. The iban validator applies it exactly and rounds only the displayed answer to six significant figures.
What are the check digits?
The two digits after the country code, calculated so that the mod-97 test passes.
Does a valid IBAN mean the account exists?
No. Only the bank can confirm that.
How long is an IBAN?
From 15 characters in Norway to 34 at most, depending on the country.
Is this iban validator free and private?
Yes. It is free, needs no account and runs in your browser, so the numbers you type are not uploaded or stored.