In recent years, the inertial measurement unit (IMU) had been widely used in precision sports and biomechanics for movement analysis and evaluation. A novel algorithm has been derived to detect countermovement jump height in real-time and achieve a mean error of 0.1 cm compared with commercial 3D tracking systems. In addition to sports ability, the correlation between IMU and various neurological diseases can also assist in diagnosing and rehabilitation for epilepsy, Parkinson's disease, and dementia.Implemented with TSMC 0.18 μm process, the algorithm is also proved to be power-efficient and area-efficient for wearable applications. To achieve a low power design, set the clock frequency to 6.5 kHz. The highest operating frequency is 22 MHz, the power consumption is 13.5 mW at 40 kHz, and the chip area is 1.153 mm by 1.150 mm. Furthermore, an application on Android Studio is also developed to demonstrate the jump height estimation algorithm for real-time applications.