Median Age in Mercer County, NJ
ACS 2024 5-Year Estimates
39.5 years
Rank #2,265/3,222 · #14 in NJ
30th
Mercer 39.5 years
NJ 40.1 years -1.5%
US 38.9 years +1.5%
Median Age Trend
Rankings →Percentile Rank Over Time
Year-over-Year Age Change
National Distribution
How Mercer County's median age of 39.5 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 Mercer County for median age.
Nearby Rankings
Full ranking →| #2,262 | Stone County, MS | 39.5 years |
| #2,263 | Butler County, MO | 39.5 years |
| #2,264 | St. Francois County, MO | 39.5 years |
| #2,265 | Mercer County, NJ | 39.5 years |
| #2,266 | Middlesex County, NJ | 39.5 years |
| #2,267 | Bernalillo County, NM | 39.5 years |
| #2,268 | Lee County, NC | 39.5 years |
About Median Age
Mercer County, New Jersey has a median age of 39.5 years, ranking #2,265 of 3,222 counties nationwide — 1.5% above the national value of 38.9 years. Within New Jersey, it ranks #14 of 21. This places it in the 30th 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.