Hawaii counties by area
Official, comparable measurements for 5 counties and county equivalents.
Understanding Hawaii’s county areas
The land-area range runs from Kalawao County at 12 mi² to Hawaii County at 4,028.4 mi². The largest has 336 times the land area of the smallest and accounts for 62.7% of the combined county land in Hawaii.
The median county-equivalent land area is 619.8 mi², above 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
Honolulu County has the most assigned water area, at 1,565.4 mi². Kalawao County has the highest water share, with water making up 77.3% 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 5 entries, water accounts for 41.5% 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 Hawaii 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 |
|---|---|---|---|---|
| 1 | Hawaii CountyGEOID 15001 | 4,028.4 mi² | 1,057.7 mi² | 20.8% |
| 2 | Maui CountyGEOID 15009 | 1,161.5 mi² | 1,236.8 mi² | 51.6% |
| 3 | Kauai CountyGEOID 15007 | 619.8 mi² | 646.5 mi² | 51.1% |
| 4 | Honolulu CountyGEOID 15003 | 600.8 mi² | 1,565.4 mi² | 72.3% |
| 5 | Kalawao CountyGEOID 15005 | 12 mi² | 40.8 mi² | 77.3% |