Median Age in Johnson County, IA
ACS 2024 5-Year Estimates
31.0 years
Rank #3,158/3,222 · #98 in IA
2th
Johnson 31.0 years
IA 38.6 years -19.7%
US 38.9 years -20.3%
Median Age Trend
Rankings →Percentile Rank Over Time
Year-over-Year Age Change
National Distribution
How Johnson County's median age of 31.0 years compares to all 3,222 U.S. counties. Values range from 21.4 years to 86.2 years.
Distribution of Median Age Across All Counties
Ranking Context
Counties ranked closest to Johnson County for median age.
Nearby Rankings
Full ranking →| #3,155 | Monroe County, IN | 31.2 years |
| #3,156 | Moore County, TX | 31.2 years |
| #3,157 | Clark County, ID | 31.1 years |
| #3,158 | Johnson County, IA | 31.0 years |
| #3,159 | Seward County, KS | 31.0 years |
| #3,160 | Roosevelt County, MT | 30.9 years |
| #3,161 | Grand Forks County, ND | 30.9 years |
About Median Age
Johnson County, Iowa has a median age of 31.0 years, ranking #3,158 of 3,222 counties nationwide — 20.3% below the national value of 38.9 years. Within Iowa, it ranks #98 of 99. This places it in the 2th percentile nationally.
The median age of the total population. Source: U.S. Census Bureau, American Community Survey 2024 5-Year Estimates. All values are estimates derived from survey samples and are subject to margin of error. For more information, see our methodology.