New Jersey counties by area

Official, comparable measurements for 21 counties and county equivalents.

Source fields preserved2026 Census Gazetteer · GEOID · ALAND · AWATER

County equivalents21

Combined land7,355 mi²

Population (2025)9,548,215

Largest by landBurlington County

46.2–221.4 mi²
224.5–301.9 mi²
309.3–356.5 mi²
427.8–483.4 mi²
518.5–799.3 mi²

Each county equivalent is shaded into one of 5 groups with equal numbers of entries, from lowest (lightest) to highest value; the map starts with land area and can switch to population density. Select a county to open its profile. 2025 Census cartographic boundaries, equal-area projection. About the maps

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. Compare with every state’s largest county.

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.

Where people live

An estimated 9,548,215 people lived in New Jersey on July 1, 2025 (+2.8% since 2020), or 2.8% of the national total in this dataset. Bergen County is the most populous county equivalent, with 977,026 residents — 10.2% of the state. The largest by land, Burlington County, has 481,439.

Across the state there are 1,298 people per square mile of land. County densities range from 15,912 in Hudson County to 200 in Salem County; the median county equivalent has 1,137. Switch the map above to density to see where the state’s population concentrates.

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 / equivalent	Land	Water	Water share	Population	Per mi²
1	Burlington CountyGEOID 34005	799.3 mi²	21.1 mi²	2.6%	481,439	602
2	Ocean CountyGEOID 34029	628.3 mi²	286.5 mi²	31.3%	673,746	1,072
3	Atlantic CountyGEOID 34001	555.6 mi²	116.3 mi²	17.3%	278,657	502
4	Sussex CountyGEOID 34037	518.5 mi²	16.9 mi²	3.2%	148,063	286
5	Cumberland CountyGEOID 34011	483.4 mi²	194.5 mi²	28.7%	157,148	325
6	Monmouth CountyGEOID 34025	468.2 mi²	193.2 mi²	29.2%	651,035	1,390
7	Morris CountyGEOID 34027	461 mi²	20.5 mi²	4.3%	524,251	1,137
8	Hunterdon CountyGEOID 34019	427.8 mi²	9.6 mi²	2.2%	131,781	308
9	Warren CountyGEOID 34041	356.5 mi²	6.1 mi²	1.7%	112,953	317
10	Salem CountyGEOID 34033	331.9 mi²	40.7 mi²	10.9%	66,280	200
11	Gloucester CountyGEOID 34015	322 mi²	14.7 mi²	4.4%	312,638	971
12	Middlesex CountyGEOID 34023	309.3 mi²	13.6 mi²	4.2%	883,335	2,856
13	Somerset CountyGEOID 34035	301.9 mi²	3.1 mi²	1%	356,486	1,181
14	Cape May CountyGEOID 34009	251.5 mi²	368.8 mi²	59.5%	93,390	371
15	Bergen CountyGEOID 34003	232.8 mi²	13.7 mi²	5.5%	977,026	4,197
16	Mercer CountyGEOID 34021	224.5 mi²	4.4 mi²	1.9%	399,289	1,779
17	Camden CountyGEOID 34007	221.4 mi²	6.1 mi²	2.7%	535,799	2,420
18	Passaic CountyGEOID 34031	186.1 mi²	12.4 mi²	6.2%	531,624	2,856
19	Essex CountyGEOID 34013	126.1 mi²	3.3 mi²	2.6%	896,379	7,109
20	Union CountyGEOID 34039	102.8 mi²	2.6 mi²	2.5%	601,863	5,857
21	Hudson CountyGEOID 34017	46.2 mi²	16.2 mi²	25.9%	735,033	15,912

How to read this table. Land and water areas are Census statistical measurements in square miles; population is the Census Bureau’s July 1, 2025 estimate, and density divides it by land area. Adding county rows can differ slightly from separately published state totals because of rounding and geographic treatment.