HI · GEOID 15003

Honolulu County area

Honolulu County, Hawaii covers 2,166.2 square miles: 600.8 square miles of land and 1,565.4 square miles of water.

Official Census measurements2026 Gazetteer · retrieved September 27, 2026
Land area600.8 mi²
Water area1,565.4 mi²
Total area2,166.2 mi²
National land rank#1622

County outline

Generalized outline of Honolulu County, Hawaii
2025 Census cartographic boundary, fitted to this frame. County maps are not at a common scale. The 2026 area measurements below come from the separate Gazetteer release. Map source and limitations.

Where Honolulu County is located

Honolulu County highlighted on a map of all U.S. county equivalents. Hawaii is repositioned as an inset at the common scale. About the maps

Area breakdown

Land accounts for 27.7% of Honolulu County’s measured area and water for 72.3%. Its combined area converts to 5,610.5 square kilometers or approximately 1,386,383 acres.

Green: land · blue: water

MeasurementSquare milesSquare kilometersAcres
Land600.7911,556.042384,506.2
Water1,565.4324,054.451,001,876.5
Total2,166.2235,610.4921,386,382.7

How Honolulu County compares

By original Census land area, Honolulu County ranks #4 of 5 in Hawaii and #1622 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.

Its land area is 0.969 times the Hawaii county-equivalent median of 619.8 square miles. It accounts for 9.4% of the combined county land area in the state.

See the complete Hawaii ranking · What counts as a county equivalent?

What stands out about Honolulu County?

Honolulu County has more land than 1,600 of the other 3,221 county equivalents in the dataset.

Land area compared with the typical county equivalent
Honolulu County600.8 mi²
Hawaii median619.8 mi²
National median604.5 mi²

A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.

Does including water change its rank?

Using land plus water places Honolulu County at #289 nationally by total area, 1,333 places closer to the top than its land rank. The water assigned to this geography moves it ahead of some county equivalents with more land.

Its water share is 72.3%, compared with a national county-equivalent median of 1.2% — 71.1 percentage points higher. This describes the statistical geography’s land/water mix, not flood exposure or developable land.

Closest positions in the national land ranking

These entries sit immediately beside Honolulu County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

Land rankCounty equivalentLand mi²Comparison
#1621Clarion County, Pennsylvania600.8Compare
#1622Honolulu County, Hawaii600.8This county
#1623St. Johns County, Florida600.7Compare

Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.

Representative coordinates

The Census internal point is 21.461365, -158.201974. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.

Source and precision

U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 1,556,040,300 m²; AWATER: 4,054,449,355 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.

Download the official county source ZIP ↗ · Methodology

Common questions

How many acres of land are in Honolulu County?

The land measurement converts to approximately 384,506 acres. Including water, total area is approximately 1,386,383 acres. One square mile equals 640 acres.

Why might another source show a different area?

Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.

Can this establish a property boundary?

No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.

Cite this county

Download the complete CSV or JSON dataset