The state of Indiana has 92 counties in total. Knox County is the oldest (founded in 1790), while Newton County is the youngest (established in 1859).

Marion County is the most populous, with a population of 903,393. Allen County (1,702 km2) has the largest land area, while Ohio County has the smallest (223 km2).

Please find a list of all Indiana counties sorted alphabetically below.

• Adams County, IN
• Allen County, IN
• Barthoomew County, IN
• Benton County, IN
• Blackford County, IN
• Boone County, IN
• Brown County, IN
• Carroll County, IN
• Cass County, IN
• Clark County, IN
• Clay County, IN
• Clinton County, IN
• Crawford County, IN
• Daviess County, IN
• De Kalb County, IN
• Dearborn County, IN
• Decatur County, IN
• Delaware County, IN
• Dubois County, IN
• Elkhart County, IN
• Fayette County, IN
• Floyd County, IN
• Fountain County, IN
• Franklin County, IN
• Fulton County, IN
• Gibson County, IN
• Grant County, IN
• Greene County, IN
• Hamilton County, IN
• Hancock County, IN
• Harrison County, IN
• Hendricks County, IN
• Henry County, IN
• Howard County, IN
• Huntington County, IN
• Jackson County, IN
• Jasper County, IN
• Jay County, IN
• Jefferson County, IN
• Jennings County, IN
• Johnson County, IN
• Knox County, IN
• Koscuisko County, IN
• Lagrange County, IN
• Lake County, IN
• LaPorte County, IN
• Lawrence County, IN
• Madison County, IN
• Marion County, IN
• Marshall County, IN
• Martin County, IN
• Miami County, IN
• Monroe County, IN
• Montgomery County, IN
• Morgan County, IN
• Newton County, IN
• Noble County, IN
• Ohio County, IN
• Orange County, IN
• Owen County, IN
• Parke County, IN
• Perry County, IN
• Pike County, IN
• Porter County, IN
• Posey County, IN
• Pulaski County, IN
• Putnam County, IN
• Randolph County, IN
• Ripley County, IN
• Rush County, IN
• Saint Joseph County, IN
• Scott County, IN
• Shelby County, IN
• Spencer County, IN
• Starke County, IN
• Steuben County, IN
• Sullivan County, IN
• Switzerland County, IN
• Tippeconoe County, IN
• Tipton County, IN
• Union County, IN
• Vanderburgh County, IN
• Vermillion County, IN
• Vigo County, IN
• Wabash County, IN
• Warren County, IN
• Warrick County, IN
• Washington County, IN
• Wayne County, IN
• Wells County, IN
• White County, IN
• Whitley County, IN