NJ · 2026 Census Gazetteer

New Jersey counties by area

Official, comparable measurements for 21 counties and county equivalents.

Source fields preservedGEOID · ALAND · AWATER
County equivalents21
Combined land7,355 mi²
Combined water1,364.2 mi²
Largest by landBurlington County

Understanding New Jersey’s county areas

The land-area range runs from Hudson County at 46.2 mi² to Burlington County at 799.3 mi². The largest has 17.3 times the land area of the smallest and accounts for 10.9% of the combined county land in New Jersey.

The median county-equivalent land area is 322 mi², below the national median of 604.5 mi². The median describes the middle of the county size distribution; it does not describe how people or development are distributed. A state with a few very large counties can have a much smaller median than its largest entry suggests.

Where water changes the picture

Cape May County has the most assigned water area, at 368.8 mi². It also has the highest water share, with water making up 59.5% of its total area. Water area and water percentage answer different questions: the first measures an amount, while the second measures the mix of land and water.

Across all 21 entries, water accounts for 15.6% of the combined total area. This is calculated from the summed land and water measurements, rather than averaging county percentages, which would give each small and large county equal weight.

Compare the largest and smallest county equivalents in New Jersey to see land, water, and total area on the same scale.

These calculations use the 2026 Census county records listed below. County-equivalent boundaries vary between states; area alone does not measure population, density, or usable land. See coverage and calculation rules.

Complete area table

Sorted from largest to smallest land area.

#County / equivalentLandWaterWater share
1Burlington CountyGEOID 34005799.3 mi²21.1 mi²2.6%
2Ocean CountyGEOID 34029628.3 mi²286.5 mi²31.3%
3Atlantic CountyGEOID 34001555.6 mi²116.3 mi²17.3%
4Sussex CountyGEOID 34037518.5 mi²16.9 mi²3.2%
5Cumberland CountyGEOID 34011483.4 mi²194.5 mi²28.7%
6Monmouth CountyGEOID 34025468.2 mi²193.2 mi²29.2%
7Morris CountyGEOID 34027461 mi²20.5 mi²4.3%
8Hunterdon CountyGEOID 34019427.8 mi²9.6 mi²2.2%
9Warren CountyGEOID 34041356.5 mi²6.1 mi²1.7%
10Salem CountyGEOID 34033331.9 mi²40.7 mi²10.9%
11Gloucester CountyGEOID 34015322 mi²14.7 mi²4.4%
12Middlesex CountyGEOID 34023309.3 mi²13.6 mi²4.2%
13Somerset CountyGEOID 34035301.9 mi²3.1 mi²1%
14Cape May CountyGEOID 34009251.5 mi²368.8 mi²59.5%
15Bergen CountyGEOID 34003232.8 mi²13.7 mi²5.5%
16Mercer CountyGEOID 34021224.5 mi²4.4 mi²1.9%
17Camden CountyGEOID 34007221.4 mi²6.1 mi²2.7%
18Passaic CountyGEOID 34031186.1 mi²12.4 mi²6.2%
19Essex CountyGEOID 34013126.1 mi²3.3 mi²2.6%
20Union CountyGEOID 34039102.8 mi²2.6 mi²2.5%
21Hudson CountyGEOID 3401746.2 mi²16.2 mi²25.9%
How to read this table. Land and water areas are Census statistical measurements in square miles. Adding county rows can differ slightly from separately published state totals because of rounding and geographic treatment.