Rank U.S. counties by population density in 2025. Compare people per square mile, exact Census population, matching land area and geographic boundaries.
New York County leads this land-area density ranking with 73,478.0 / sq. mi.. The reference population is July 1, 2025.
Which counties have the highest population density?
New York County, New York leads at 73,478.0 people per square mile of land. Its 1,664,862 residents occupy a source land area of 22.658 square miles. Kings County, New York follows at 38,254.5 people per square mile.
The largest-population county, Los Angeles County, California, has a density of 2,387.7 people per square mile. Population size and density therefore measure different attributes: one counts residents, while the other divides by compatible land area.
County equivalents and dense urban boundaries
A county equivalent can be a compact independent city or an extensive rural county. The geographic units have the same statistical level in the source but can have very different physical sizes.
New York City’s borough counties are separately identified county equivalents. Their densities should not be averaged to obtain the density of the entire city; sum matching populations and land areas before dividing.
Comparison universe: 3,144 U.S. counties and county equivalents. Source: PEP Vintage 2025. Population date: July 1, 2025. Growth interval: July 1, 2024–2025. Ties share a competition rank; subsequent ranks skip tied positions. Filters produce a subset of this universe and do not change the national profile rank.
Density equals the July 1, 2025 resident population divided by 2025 Gazetteer land area. Original land area in square meters is converted using 2,589,988.110336 square meters per square mile. Water is excluded; unrounded land areas and population values determine the order. Displayed density is rounded to one decimal place.
The matching area is joined by official geographic code. 0 records in this eligible universe are excluded because a valid positive land-area denominator is unavailable. A missing denominator is not a zero density. Density refers to the whole geography, rather than a built-up area, a housing parcel or a person's living conditions.
Sources, calculation rules and downloadable results
Source: co-est2025-alldata.csv, Census Population Estimates Program, Vintage 2025, variables POPESTIMATE2024 and POPESTIMATE2025. Density additionally uses 2025 Gazetteer ALAND joined by official code. The retained source snapshot is pep-2025-r1; calculations use unrounded values.
Density order divides resident population by compatible land area in square miles. Equal unrounded metric values share a competition rank, and the following rank skips the tied positions. Display rounding can make different underlying values look identical; the table order uses the originals.
Export visible rows after filtering to preserve the displayed subset. Use complete dataset downloads for all observations, or population research tools for a longer comparison. A ranking is a dated descriptive result, not an official forecast. Publication vintages can revise earlier years; retain the release identifier with your research.
