The Smart Attendance System is an advanced IoT-based project that uses an ESP32 microcontroller and a 4G LTE module (SIM A7670C / SIM7600) to record and send attendance data directly to a cloud server using HTTP POST requests. This system completely eliminates the need for Wi-Fi, making it ideal for remote locations, construction sites, schools, factories, and offices where Wi-Fi access may be limited or unavailable. When a user scans an RFID card, the ESP32 reads the card’s unique ID and sends the information—along with the device ID and timestamp—to the cloud server via the 4G network. The server (built using PHP + MySQL) stores the data securely and can display it in a dashboard for real-time monitoring. This project provides end-to-end connectivity, from device hardware to cloud database, including: Complete hardware connections and circuit wiring Arduino/ESP32 source code (copy-paste ready) Server-side PHP & MySQL script for database integration Troubleshooting t