Tachikawa is a city situated in the western portion of the Tokyo Metropolis in Japan. It covers a total area of 24.36 square kilometres, which is approximately 9.41 square miles.
As of March 1, 2021, the city had an estimated population of 184,383 residents living in 93,428 households. The population density of the area is recorded at 7,600 persons per square kilometre.