Mercer County, NJ Demographics
Mercer County, NJ is the 12th most populous of 21 counties in New Jersey, with 387,340 residents across 224 square miles. That is about 1,726 people per square mile.
At the 2020 census
| Population | 387,340 |
|---|---|
| Land area | 224 sq mi |
| Density | 1,726 / sq mi |
Data: 2020 Census · American Community Survey 2024
How Mercer County compares to the US
We're computing this county's comparison table — check back shortly. Population, land area, and density above are already exact.
Central Location: Mercer County, NJ
Measured from the county's main population center using 2020 census blocks.
We're computing the drive-time and radius areas around Mercer County, NJ — check back shortly. Meanwhile you can drop a pin anywhere in the radius tool.
Census tracts in Mercer County, NJ
| Name | Population | Sq mi | Per sq mi |
|---|---|---|---|
| Census Tract 44.04 | 7,787 | 1.3 | 6,167 |
| Census Tract 44.07 | 7,733 | 2.0 | 3,931 |
| Census Tract 25 | 7,579 | 4.0 | 1,914 |
| Census Tract 32.01 | 7,475 | 2.9 | 2,606 |
| Census Tract 35 | 7,331 | 2.0 | 3,643 |
| Census Tract 33.01 | 7,112 | 4.6 | 1,544 |
| Census Tract 37.03 | 7,108 | 1.5 | 4,838 |
| Census Tract 43.11 | 6,975 | 1.7 | 4,064 |
| Census Tract 38 | 6,874 | 30.4 | 226 |
| Census Tract 28 | 6,725 | 0.9 | 7,516 |
| Census Tract 45.01 | 6,474 | 0.6 | 10,615 |
| Census Tract 27.02 | 6,454 | 2.1 | 3,096 |
| Census Tract 33.03 | 6,419 | 2.2 | 2,906 |
| Census Tract 4 | 6,305 | 0.2 | 31,419 |
| Census Tract 30.01 | 6,287 | 10.1 | 625 |
| Census Tract 43.07 | 6,218 | 3.3 | 1,910 |
| Census Tract 30.03 | 6,209 | 3.1 | 2,022 |
| Census Tract 39.04 | 6,122 | 6.2 | 987 |
| Census Tract 22 | 6,109 | 0.4 | 13,593 |
| Census Tract 42.04 | 6,054 | 5.6 | 1,086 |
| Census Tract 30.06 | 5,965 | 1.9 | 3,189 |
| Census Tract 44.03 | 5,900 | 1.2 | 4,784 |
| Census Tract 30.04 | 5,811 | 1.6 | 3,641 |
| Census Tract 44.06 | 5,771 | 3.1 | 1,877 |
| Census Tract 37.08 | 5,718 | 3.7 | 1,563 |
| Census Tract 30.02 | 5,691 | 2.3 | 2,456 |
| Census Tract 40 | 5,686 | 0.7 | 8,427 |
| Census Tract 21 | 5,670 | 0.4 | 15,725 |
| Census Tract 32.02 | 5,643 | 3.3 | 1,704 |
| Census Tract 43.14 | 5,526 | 6.1 | 911 |
| Census Tract 30.09 | 5,430 | 1.8 | 3,042 |
| Census Tract 30.08 | 5,389 | 1.5 | 3,487 |
| Census Tract 29.04 | 5,214 | 2.9 | 1,777 |
| Census Tract 18 | 5,193 | 0.4 | 11,599 |
| Census Tract 43.06 | 5,108 | 7.1 | 721 |
| Census Tract 3 | 5,068 | 0.3 | 20,269 |
| Census Tract 6 | 5,052 | 0.2 | 20,748 |
| Census Tract 5 | 5,050 | 0.2 | 32,075 |
| Census Tract 43.09 | 4,980 | 13.4 | 372 |
| Census Tract 29.02 | 4,869 | 1.9 | 2,527 |
| Census Tract 43.16 | 4,791 | 5.4 | 887 |
| Census Tract 26.01 | 4,785 | 0.7 | 6,528 |
| Census Tract 42.05 | 4,671 | 3.7 | 1,277 |
| Census Tract 44.08 | 4,637 | 3.2 | 1,466 |
| Census Tract 27.01 | 4,586 | 1.0 | 4,645 |
| Census Tract 31 | 4,516 | 1.2 | 3,902 |
| Census Tract 39.05 | 4,495 | 21.4 | 210 |
| Census Tract 43.13 | 4,390 | 0.9 | 4,775 |
| Census Tract 2 | 4,349 | 0.2 | 22,517 |
| Census Tract 26.02 | 4,348 | 0.7 | 5,829 |
| Census Tract 42.03 | 4,199 | 6.3 | 664 |
| Census Tract 44.09 | 4,117 | 6.1 | 675 |
| Census Tract 13 | 3,963 | 0.9 | 4,477 |
| Census Tract 9 | 3,942 | 0.5 | 7,626 |
| Census Tract 7 | 3,907 | 0.1 | 30,381 |
| Census Tract 14.01 | 3,884 | 0.4 | 10,681 |
| Census Tract 12 | 3,819 | 0.5 | 7,319 |
| Census Tract 37.06 | 3,737 | 2.0 | 1,909 |
| Census Tract 29.03 | 3,561 | 2.1 | 1,662 |
| Census Tract 17 | 3,524 | 0.4 | 9,344 |
| Census Tract 43.12 | 3,521 | 5.4 | 658 |
| Census Tract 43.15 | 3,485 | 2.8 | 1,234 |
| Census Tract 30.07 | 3,394 | 0.8 | 4,304 |
| Census Tract 1 | 3,354 | 0.5 | 7,096 |
| Census Tract 36.01 | 3,350 | 0.6 | 5,444 |
| Census Tract 11.02 | 3,237 | 0.2 | 15,004 |
| Census Tract 36.02 | 3,129 | 0.7 | 4,692 |
| Census Tract 10 | 2,999 | 0.3 | 8,781 |
| Census Tract 34 | 2,810 | 0.9 | 3,289 |
| Census Tract 8 | 2,808 | 0.2 | 14,751 |
| Census Tract 39.03 | 2,802 | 1.0 | 2,916 |
| Census Tract 15 | 2,708 | 0.2 | 11,172 |
| Census Tract 37.04 | 2,679 | 1.3 | 2,015 |
| Census Tract 42.06 | 2,443 | 0.6 | 4,217 |
| Census Tract 11.01 | 2,377 | 0.3 | 8,210 |
| Census Tract 39.02 | 1,918 | 0.7 | 2,650 |
| Census Tract 33.04 | 1,912 | 7.6 | 253 |
| Census Tract 14.02 | 1,754 | 0.1 | 12,321 |
| Census Tract 20 | 1,595 | 0.2 | 8,062 |
| Census Tract 19 | 1,500 | 0.3 | 5,439 |
| Census Tract 9800 | 1,479 | 0.0 | 58,462 |
| Census Tract 37.07 | 1,402 | 2.6 | 530 |
| Census Tract 16 | 1,225 | 0.1 | 10,467 |
| Census Tract 45.02 | 1,154 | 0.5 | 2,200 |
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Metro areas containing Mercer County
About this page
This page shows demographics for a US county from the 2020 census and the American Community Survey: population, land area, density, urban share, and how the county compares to national averages for income, housing, age, and more.
Counties subdivide into census tracts, listed below with their populations. The drive-time and radius tables measure the population around the county's main population center.