Median Age in Johnson County, IL
ACS 2024 5-Year Estimates
41.4 years
Rank #1,680/3,222 · #65 in IL
48th
Johnson 41.4 years
IL 39.0 years +6.2%
US 38.9 years +6.4%
Median Age Trend
Rankings →Percentile Rank Over Time
Year-over-Year Age Change
National Distribution
How Johnson County's median age of 41.4 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 →| #1,677 | Union County, AR | 41.4 years |
| #1,678 | Jones County, GA | 41.4 years |
| #1,679 | Adams County, IL | 41.4 years |
| #1,680 | Johnson County, IL | 41.4 years |
| #1,681 | Clay County, IN | 41.4 years |
| #1,682 | Carter County, KY | 41.4 years |
| #1,683 | Eaton County, MI | 41.4 years |
About Median Age
Johnson County, Illinois has a median age of 41.4 years, ranking #1,680 of 3,222 counties nationwide — 6.4% above the national value of 38.9 years. Within Illinois, it ranks #65 of 102. This places it in the 48th 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.