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Johnson County, Kansas

Johnson County profile, demographic data, and geographic information.

Johnson County is a county located in Kansas, United States of America. As of official census estimates, it has a reported population of 636,906. The land area covers 473.63 sq mi. [1]

Local Government Administration U.S. Census Bureau GMAF

County Of Johnson County
Official Title: Management Intern
Address: 111 S CHERRY ST, STE 3300, OLATHE KS 66061-3487

Demographics & Population

Demographic Metric Estimate / Count Margin of Error Survey Period / Source
Total Population (2025 PEP Estimate) 636,906 — 2025 / Census
Median Age 38.6 yrs ±0.2 2020-2024 / Census ACS 5-Year 2024
Total Households 249,531 ±1,006 2020-2024 / Census ACS 5-Year 2024
Source: U.S. Census Bureau (PEP, ACS 5-Year).

Housing & Real Estate Profile

Housing Metric Estimate / Value Margin of Error
Total Housing Units 259,655 ±181
Occupied Housing Units 249,531 ±1,006
Vacant Housing Units 10,124 ±940
Median Home Value $391,200 ±$3,069
Median Gross Rent $1,434 ±$16
Source: U.S. Census Bureau ACS 5-Year (2020-2024).

Economy & Workforce

Economic Metric Estimate / Value Margin of Error
Median Household Income $109,208 ±$1,170
Per Capita Income $60,137 ±$1,345
Poverty Rate 5.4% ±0.3%
Population Below Poverty Level 33,284 ±1,998
Unemployment Rate 3.2% ±0.3%
Civilian Labor Force, Employed 341,320 ±2,227
Broadband Internet Rate 95.9% ±0.4%
Source: U.S. Census Bureau ACS 5-Year (2020-2024).

Climate & Weather Observations

NOAA Monthly Climate Normals

Observation Station: Climate data reflects NOAA 1991–2020 standard normals recorded at OLATHE 3E, KS US, located 3.3 miles from Johnson County. Local microclimates, topography, and elevation may cause municipal conditions to differ.
Month High (°F) Low (°F) Mean (°F) Precip (in) Snow (in)
January 38.7° 20.0° 29.3° 1.28" 3.9"
February 44.3° 23.9° 34.1° 1.73" 3.3"
March 54.9° 33.7° 44.3° 2.48" 1.4"
April 65.1° 43.9° 54.5° 4.12" 0.3"
May 74.5° 55.5° 65.0° 5.26" 0.0"
June 83.6° 64.9° 74.3° 5.23" 0.0"
July 88.2° 69.4° 78.8° 4.75" 0.0"
August 86.8° 66.9° 76.9° 4.46" 0.0"
September 79.1° 58.4° 68.8° 4.25" 0.0"
October 67.7° 46.7° 57.2° 3.05" 0.3"
November 54.3° 34.6° 44.5° 2.37" 1.2"
December 42.5° 24.6° 33.5° 1.75" 3.4"
Source: NOAA U.S. Climate Normals (1991–2020).

Local Weather Forecast

Weather forecast data is currently unavailable in the local cache.

Sources & Data Provenance

  1. Geographic Classification & Identifiers: U.S. Census Bureau Gazetteer (2026) and TIGER/Line Shapefiles. GEOID: 20091. • Official Source Dataset →
  2. Socioeconomic & Housing Metrics: U.S. Census Bureau American Community Survey (ACS) 5-year estimates and Population Estimates Program (PEP). Margin of Error (MOE) intervals are reported where published; suppressed values are never estimated or replaced with false zeros.
  3. Civic Directory Datasets: Centers for Medicare & Medicaid Services (CMS Hospital Directory), National Center for Education Statistics (NCES IPEDS Postsecondary Directory), and Institute of Museum and Library Services (IMLS Public Libraries Survey). Airport landing facilities are provided by airport-data.com.
  4. Weather & Climate Observations: National Oceanic and Atmospheric Administration (NOAA) U.S. Climate Normals 1991–2020 and National Weather Service (NWS) point forecasts.