使用方法

Type or paste an IBAN into the input field.
Read the success or error alert for the mod-97 checksum and country-length result.
Review the detail table showing country code, check digits, BBAN, and expected length.
Use the share button to send a pre-filled link to a colleague.

示例

DE89 3704 0044 0532 0130 00 passes both mod-97 and the 22-character German length check.
An IBAN with the wrong length for its country prefix triggers an error citing the expected vs actual character count.