Johnson -- U.S. County in Missouri Population (2000): 48258 Housing Units (2000): 18886 Land area (2000): 830.439922 sq. miles (2150.829433 sq. km) Water area (2000): 2.586594 sq. miles (6.699248 sq. km) Total area (2000): 833.026516 sq. miles (2157.528681 sq. km) Located within: Missouri (MO), FIPS 29 Location: 38.745484 N, 93.796313 W Headwords: Johnson Johnson, MO Johnson County Johnson County, MO