Johnson County, Indiana

Johnson County, Indiana
Johnson County Courthouse in Franklin, Indiana
Location within the U.S. state of Indiana
Coordinates: 39°29′N 86°06′W / 39.49°N 86.1°W / 39.49; -86.1
Country United States
State Indiana
Founded1823
SeatFranklin
Largest cityGreenwood
Area
 • Total
321.79 sq mi (833.4 km2)
 • Land320.43 sq mi (829.9 km2)
 • Water1.36 sq mi (3.5 km2)  0.42%
Population
 (2020)
 • Total
161,765
 • Estimate 
(2024)
170,614
 • Density504.84/sq mi (194.92/km2)
Time zoneUTC−5 (Eastern)
 • Summer (DST)UTC−4 (EDT)
Congressional district6th
Websitewww.co.johnson.in.us
Indiana county number 41

Johnson County is a county located in the U.S. state of Indiana. As of 2020, the population was 161,765. The county seat is Franklin. Johnson County is included in the Indianapolis-Carmel-Anderson, IN Metropolitan Statistical Area.