public class UserApiTest
import mrchecker.framework.common.connector.CCN2; import mrchecker.framework.common.connector.dto.RestResponse;
git clone https://github.com/mrchecker/ccn2.git cd ccn2 pip install -r requirements.txt # Python example mrchecker ccn2
def detect_brand(card_num: str) -> str: first6 = card_num[:6] if card_num[0] == '4': return 'Visa' if card_num[:2] in ['51','52','53','54','55'] or (2221 <= int(first6) <= 2720): return 'Mastercard' if card_num[:2] in ['34','37']: return 'Amex' if card_num[:4] == '6011' or card_num[:3] in ['644','645','646','647','648','649'] or card_num[:2] == '65': return 'Discover' return 'Unknown'
⚠️ Only use on cards you own or have explicit written permission to test. Unauthorized use is illegal. public class UserApiTest import mrchecker
The CCN2 module is built on three primary pillars:
| Prefix range | Brand | Length | CVV length | |--------------|-------------|--------|-------------| | 4 | Visa | 13,16 | 3 | | 51–55, 2221–2720 | Mastercard | 16 | 3 | | 34, 37 | Amex | 15 | 4 | | 6011, 644–649, 65 | Discover | 16,19 | 3 | '55'] or (2221 <
[RESULT] INVALID (Luhn fail) Brand: Visa Length: 16
Example: 4532 1234 5678 9123 (invalid for demo) - Double every second digit from right - Sum digits (if >9, sum digits of result) - Total mod 10 must equal 0
def mrchecker_ccn2(card_number: str) -> dict: # implementation (see section 5) pass