For pre-built classes and libraries, you can explore repositories on GitHub like: PHP-Credit-Card-Validator by inacho. PHP-Credit-Card-Checker for core PHP implementations. PHP-Credit-Card-Checker/index.php at master - GitHub
To develop a credit card checker script in PHP, you can offline validation Luhn algorithm regular expressions (regex) to identify card types like Visa or Mastercard Core Components of a CC Checker Script cc checker script php
The script analyzes the HTTP response code and body to determine "live" status: For pre-built classes and libraries, you can explore