The exact location of the Barhi town is at 24.3° North and 85.42° East. The mean elevation of the town is 374 metres (1227 feet). The Barakar River flows at a distance of two miles from Barhi. The town is located at the crossing of National Highway 2 (Grand Trunk Road) and National Highway 33. All main buses on the Ranchi-Gaya, Ranchi-Patna, Dhanbad-Patna and Dhanbad-Gaya routes travel through Barhi. At a small distance from this town, are located the Tilayia Dam of DVC and the Hazaribagh National Park.
As per the 2001 India census, Barhi has a population of 9933. Males amount to 53% of the population and females make up 47%. The town has a mean literacy rate of 60%, higher than the nationwide standard of 59.5%. 62% of the males and 38% of the females are literate. 18% of the population consists of children less than six years of age.