Chiba is the capital city of Chiba Prefecture, Japan. It sits about 40 kilometres east of the centre of Tokyo on Tokyo Bay. The city becam…Chiba is the capital city of Chiba Prefecture, Japan. It sits about 40 kilometres east of the centre of Tokyo on Tokyo Bay. The city became a government-designated city in 1992. In March 2025, its population was 983,045, with a population density of 3,617 people per km. The city has an area of 271.77 square kilometres.