Ventilator-Induced Lung Injury (VILI) is a significant concern in mechanical ventilation, as inaccurate airflow can lead to severe complications and worsen a ventilated patient’s conditions. To prevent the risk of VILI, accurate monitoring of gas flow rates delivered to ventilated patients is essential. This paper presents the design and prototyping of a thermal flow meter for low-cost mechanical ventilation systems. The sensor utilizes a hot wire anemometry technique, employing a Negative Temperature Coefficient (NTC) thermistor operating in constant temperature mode to measure airflow accurately. The system features a closed-loop control circuit that continuously adjusts the electrical current supplied to the sensing element, compensating for cooling effects and stabilizing the temperature despite variations in airflow. The prototype is calibrated using a test bench to ensure reliable flow rate measurements. These measurements are transmitted to a mobile application via Wi-Fi. The affordability, real-time feedback, and IoT integration contributes to the proposed advancements in mechanical ventilation sensor technology by optimizing respiratory care.