The server handles incoming API requests from your distributed software and checks them against a database of valid keys. 1. Database Schema

A modern license key system consists of three distinct engines:

This code verifies the license key by comparing it to the expected license key, which is generated using the same algorithm as before.

if ($httpCode !== 200) return false;

A search for "PHP License System" on GitHub yields thousands of results, but the "hot" repositories share common traits that appeal to modern developers.