Nishitokyo is a city located in the western portion of Tokyo Metropolis, Japan. It is one of the municipalities that make up the western suburbs of the Tokyo metropolitan area.
As of 1 January 2021, the city had an estimated population of 206,047, with a population density of about 13,000 persons per square kilometre. Its total area is 15.75 square kilometres (6.08 square miles), making it a comparatively compact and densely populated city.