Peatland fire releases a huge amount of carbon emissions to the atmosphere causing air pollution and soil damage. The total emission released to the air could be calculated through the amount of peat that burned downor known as depth of the burn. In this research, a device was developed to detectthe smouldering spread of peat both laterally and vertically through the subsidence. The device was operated using a microcontroller and a laser ranging module. This paper presents a preliminary result on the device capability on measuring several objects such as flat surface and semi-spherical objects.