Hachiōji is a city located in the western portion of the Tokyo Metropolis in Japan. As of March 31, 2021, it has an estimated population of 561,344 and a population density of 3,000 persons per square kilometer. The city covers a total area of 186.38 km² (71.96 sq mi).
The city is notable for being the most populous city in Tokyo outside of the special wards. In 2015, it was designated as a core city for the first time in Tokyo. Additionally, Hachiōji was the second city in Tokyo Prefecture to implement the municipal system following Tokyo City.