Clarke County is located in the northeastern part of the U.S. state of Georgia. As of the 2020 census, the population was 128,671. Its county seat is Athens, with which it is a consolidated city-county. Clarke County is included in the Athens-Clarke County, GA Metropolitan Statistical Area, which is also included in the Atlanta-Athens-Clarke County-Sandy Springs, GA Combined Statistical Area.

The Athens-Clarke County Metropolitan Statistical Area, as defined by the United States Census Bureau, is an area consisting of four counties - Clarke, Madison, Oconee, and Oglethorpe - in northeastern Georgia, anchored by the city of Athens. As of the 2020 census, the MSA had a population of 215,479.