Median Age in DeKalb County, IL
ACS 2024 5-Year Estimates
32.7 years
Rank #3,091/3,222 · #100 in IL
4th
DeKalb 32.7 years
IL 39.0 years -16.2%
US 38.9 years -15.9%
Median Age Trend
Rankings →Percentile Rank Over Time
Year-over-Year Age Change
National Distribution
How DeKalb County's median age of 32.7 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 DeKalb County for median age.
Nearby Rankings
Full ranking →| #3,088 | Coryell County, TX | 32.8 years |
| #3,089 | Midland County, TX | 32.8 years |
| #3,090 | Kern County, CA | 32.7 years |
| #3,091 | DeKalb County, IL | 32.7 years |
| #3,092 | LaGrange County, IN | 32.7 years |
| #3,093 | Boone County, MO | 32.7 years |
| #3,094 | Holmes County, OH | 32.7 years |
About Median Age
DeKalb County, Illinois has a median age of 32.7 years, ranking #3,091 of 3,222 counties nationwide — 15.9% below the national value of 38.9 years. Within Illinois, it ranks #100 of 102. This places it in the 4th 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.