The title asks for IBAN KR123456789012. That string is not a valid IBAN (Korea’s published format is longer; this value fails the checksum). BankDataStack POST /api/v1/iban/validate with header X-API-Key returns 400 on a bad checksum. Use the official sample GB82WEST12345698765432 to see a passing parse.
Starter is $49.99/mo (1,000 calls, then $0.002) with a 7-day trial. No live MCP (DNS for mcp.bankdatastack.com failed). Docs: bankdatastack.com/docs. Register: bankdatastack.com/register.
Request: official UK WEST (valid)
curl -X POST https://www.bankdatastack.com/api/v1/iban/validate \
-H "X-API-Key: YOUR_API_KEY" -H "Content-Type: application/json" \
-d '{"iban": "GB82WEST12345698765432"}'Response: official /docs sample
{
"status": "success",
"data": {
"iban": "GB82WEST12345698765432",
"valid": true,
"countryCode": "GB",
"checkDigits": "82",
"bban": "WEST12345698765432"
}
}Request: the title IBAN (expect 400)
curl -X POST https://www.bankdatastack.com/api/v1/iban/validate \
-H "X-API-Key: YOUR_API_KEY" -H "Content-Type: application/json" \
-d '{"iban": "KR123456789012"}'Format errors return 422; a bad checksum returns 400. That is the contract — do not invent a Shinhan account from a padded number.
Go live
1. Register — 7-day trial.
2. POST the official GB sample, then your real IBAN.
