Data / Rankings / Population density / Counties in New Jersey

Counties in New Jersey by population density, 2025

Hudson County had the highest population density of 21 counties in 2025, at 6,143.8 inhabitants per km². Salem County had the lowest, at 77.1 inhabitants per km². The median was 439.1 inhabitants per km² and the figure for New Jersey was 501.2 inhabitants per km². Source: the U.S. Census Bureau.

Highest6,143.8Hudson County
Lowest77.1Salem County
Median439.121 counties
New Jersey501.2History

All counties, 2025

CSVChart (SVG)

Hudson CountyHudson County: 6,143.8 inhabitants per km²6,143.8Essex CountyEssex County: 2,745 inhabitants per km²2,745Union CountyUnion County: 2,261.2 inhabitants per km²2,261.2Bergen CountyBergen County: 1,620.4 inhabitants per km²1,620.4Passaic CountyPassaic County: 1,102.8 inhabitants per km²1,102.8Middlesex CountyMiddlesex County: 1,102.6 inhabitants per km²1,102.6Camden CountyCamden County: 934.5 inhabitants per km²934.5Mercer CountyMercer County: 686.8 inhabitants per km²686.8Monmouth CountyMonmouth County: 536.9 inhabitants per km²536.9Somerset CountySomerset County: 456 inhabitants per km²456Morris CountyMorris County: 439.1 inhabitants per km²439.1Ocean CountyOcean County: 414 inhabitants per km²414Gloucester CountyGloucester County: 374.9 inhabitants per km²374.9Burlington CountyBurlington County: 232.6 inhabitants per km²232.6Atlantic CountyAtlantic County: 193.7 inhabitants per km²193.7Cape May CountyCape May County: 143.4 inhabitants per km²143.4Cumberland CountyCumberland County: 125.5 inhabitants per km²125.5Warren CountyWarren County: 122.3 inhabitants per km²122.3Hunterdon CountyHunterdon County: 118.9 inhabitants per km²118.9Sussex CountySussex County: 110.3 inhabitants per km²110.3Salem CountySalem County: 77.1 inhabitants per km²77.1
inhabitants per km². Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-09.

Full ranking

RankCounties2025
inhabitants per km²		Change on 2024
1Hudson County6,143.8+0.5%
2Essex County2,745+0.6%
3Union County2,261.2+0.5%
4Bergen County1,620.4+0.4%
5Passaic County1,102.8+0.1%
6Middlesex County1,102.6+0.2%
7Camden County934.5+0.4%
8Mercer County686.8+0.5%
9Monmouth County536.9+0.4%
10Somerset County456+0.4%
11Morris County439.1+0.6%
12Ocean County414+0.8%
13Gloucester County374.9+0.4%
14Burlington County232.6+0.8%
15Atlantic County193.7+0.1%
16Cape May County143.4-0.7%
17Cumberland County125.5+0.5%
18Warren County122.3+0.5%
19Hunterdon County118.9+0.5%
20Sussex County110.3+0.4%
21Salem County77.1+0.5%

Other periods

About this ranking

Resident population divided by land area in km². World Bank figures use mid-year population and land area excluding inland water.

United States: Census Bureau population estimates for 1 July divided by land area (water excluded) from the latest Census Gazetteer files. US tables often give people per square mile; multiply persons per km² by 2.59 to compare.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². https://www2.census.gov/programs-surveys/popest/datasets/2020-2025/. Retrieved 2026-10-09.

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Questions

Which county has the highest population density?

Hudson County, with 6,143.8 inhabitants per km² in 2025, according to the U.S. Census Bureau.

Which county has the lowest population density?

Salem County, with 77.1 inhabitants per km² in 2025.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program resident population on 1 July divided by land area from the latest Census Gazetteer files, persons per km². Retrieved 2026-10-09.

Population density: other rankings

Counties in New Jersey: more rankings