County Maps US

Johnson County, Indiana

A county in Indiana, ranked 11 of 92 by population.

CountyFIPS 18081

Within Indiana
Johnson County, highlighted, with the areas around it. Boundaries generalised from the 2025 Census cartographic boundary file; neighbour fills carry no data. The dot marks Franklin, the county seat, located via the 2025 Census Gazetteer.

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Population
174,262
+12,025 (+7.4%) since 2020
Land area
320.4
square miles. A further 0.4% of the total area is water
Population density
544
people per square mile, computed rather than published
County seat
Franklin
Seat of county government.
Established
1823
202 years ago
Largest city
Greenwood city
Population 69,349.

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; Wikidata (CC0), Wikidata. Retrieved 30 August 2026.

Satellite view

Aerial imagery of Johnson County with its boundary drawn on top. A map shows you the shape; this shows you what is inside it, and which side of the line a place falls on.

Aerial view of Johnson County, Indiana from the USGS National Map, with its boundary outlined
Imagery: USGS National Map, USGS Imagery Only, public domain, requested from USGS by your browser when you reach this point on the page, at 645 by 800 pixels. The boundary is the 2025 Census cartographic boundary file, reprojected to Web Mercator to match the imagery. You can also open the USGS National Map viewer.

Where Johnson County ranks

Position among the 92 counties of Indiana, and among all 3,144 US counties and county-equivalents. Computed from the figures on this page.

MeasureValueIn IndianaNationally
Population174,26211th of 92404th of 3,144
Land area320.4 sq mi75th of 922,760th of 3,144
Population density544 per sq mi8th of 92266th of 3,144
Median household income$90,4545th of 92291st of 3,143

Full data for Johnson County

Every figure below is attributed to the Census Bureau product it came from, with the vintage of that product.
MeasureValueSource and vintage
Population174,262Vintage 2025 Population Estimates
Population in 2020162,237Vintage 2025 Population Estimates
2020 estimates base?161,776Vintage 2025 Population Estimates
Land area320.4 sq mi2025 Gazetteer Files
Water area1.4 sq mi2025 Gazetteer Files
Total area321.8 sq mi2025 Gazetteer Files
Population density?544 per sq miComputed: Vintage 2025 estimates divided by 2025 Gazetteer land area
Median household income$90,454American Community Survey 2020-2024 5-Year Estimates
Median home value$284,600American Community Survey 2020-2024 5-Year Estimates
Median age38.0American Community Survey 2020-2024 5-Year Estimates
Households62,554American Community Survey 2020-2024 5-Year Estimates
Housing units65,915American Community Survey 2020-2024 5-Year Estimates

Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026. Population density is computed here, not published: it divides the Vintage 2025 population estimate by the 2025 Gazetteer land area, which are two different Census products. Retrieved 30 August 2026.

How the population changed

The Census Bureau publishes the components behind an estimate, not just the total. For the year to July 2025:

Births minus deaths
+384
1,907 births, 1,523 deaths
Net migration
+2,876
More people moved in than moved out.

Source: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026. Retrieved 30 August 2026.

The 5 areas bordering Johnson County

Ordered by the length of the border actually shared, which the Census Bureau publishes in its county adjacency file and which no other county reference presents.

Bordering areaStateShared borderPopulation
Morgan CountyIndiana20 mi74,967
Shelby CountyIndiana20 mi45,882
Marion CountyIndiana16 mi992,196
Brown CountyIndiana8.9 mi15,777
Bartholomew CountyIndiana7.2 mi85,729

Source: US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. Retrieved 30 August 2026.

All 92 counties of Indiana

Open the interactive Indiana county map, or jump straight to any of them.

Data on this page last rebuilt 30 August 2026. How these figures are produced.