IBAN Validator
Validate an IBAN with the mod-97 checksum and read its country and length.
Check an IBAN’s checksum
An IBAN packs a country code, check digits, and the account details into one string, guarded by a mod-97 checksum that catches almost every typo. This validator applies that check and reports the country and length.
GB82 WEST 1234 5698 7654 32 is a valid 22-character United Kingdom IBAN. The tool rearranges the string, converts letters to numbers, and confirms the remainder is 1 — the test every bank runs first.
Standards-correct and private
It implements the ISO 7064 mod-97 algorithm exactly, chunk by chunk to avoid overflow, and runs entirely in your browser.
Frequently Asked Questions
How is an IBAN validated?
By the ISO 7064 mod-97 rule: move the first four characters to the end, turn letters into numbers, and the whole thing must leave a remainder of 1 when divided by 97.
Does valid mean the account exists?
No — it means the number is well-formed and the checksum passes. Only the bank can confirm the account is real and open.
Is my IBAN uploaded?
No. The check runs entirely in your browser and nothing you enter is stored or sent anywhere.
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