In 2019, Mercer County, NJ had a population of 367k people with a median age of 38.8 and a median household income of $79,492. Between 2018 and 2019 the population of Mercer County, NJ declined from 369,811 to 367,430, a −0.644% decrease and its median household income declined from $80,632 to $79,492, a −1.41% decrease.
The 5 largest ethnic groups in Mercer County, NJ are White (Non-Hispanic) (48.2%), Black or African American (Non-Hispanic) (19.4%), Asian (Non-Hispanic) (11.8%), White (Hispanic) (11.5%), and Other (Hispanic) (5.28%). 0% of the households in Mercer County, NJ speak a non-English language at home as their primary language, and 87.5% of the residents in Mercer County, NJ are U.S. citizens.
In 2019, the median property value in Mercer County, NJ was $291,600, and the homeownership rate was 62.6%. Most people in Mercer County, NJ drove alone to work, and the average commute time was 27.8 minutes. The average car ownership in Mercer County, NJ was 2 cars per household.