Johnson -- U.S. County in Indiana Population (2000): 115209 Housing Units (2000): 45095 Land area (2000): 320.193380 sq. miles (829.297013 sq. km) Water area (2000): 1.363657 sq. miles (3.531854 sq. km) Total area (2000): 321.557037 sq. miles (832.828867 sq. km) Located within: Indiana (IN), FIPS 18 Location: 39.513686 N, 86.100823 W Headwords: Johnson Johnson, IN Johnson County Johnson County, IN