Requires PHP 7.4+ with the cURL extension.
export CHECKNUMBER_API_KEY="YOUR_API_KEY"
php facebook_checker.php # reads numbers.txt (one E.164 number per line)Submits to POST /v1/tasks (task_type=facebook), polls POST /v1/gettasks, downloads results. Full docs: https://docs.checknumber.ai/facebook-bulk-number-checker