1 mi² = 258.999 ha (square mile → hectare)
1 mi² = 258.999 ha
1 square mile equals 258.999 hectares. To convert square miles to hectares, multiply the square mile value by 258.999. For quick reference: 1 mi² = 258.999 ha, 5 mi² = 1294.99 ha, 10 mi² = 2589.99 ha, 100 mi² = 25899.9 ha.
Hectares = Square miles × 258.999Square miles to hectares multiplies by 258.9988110336 (exact). Yellowstone's 3,472 sq mi is about 899,000 ha. Used when US-surveyed land areas feed international datasets — the FAO, IUCN, and most scientific literature use hectares regardless of where the land sits. Keep three significant figures unless the source data genuinely supports more.
Start with your value in square miles.
Multiply the square mile value by 258.999. This is the exact conversion factor from square miles to hectares.
The product is your value in hectares. For example, 5 mi² × 258.999 = 1294.99 ha.
The exact factor from square miles to hectares is 258.999.
Hectares = Square miles × 258.999
Fifty common reference values, hand-picked for skim utility. Use the calculator above for any value not listed.
| Square miles (mi²) | Hectares (ha) |
|---|---|
| 0.1 mi² | 25.9 ha |
| 0.25 mi² | 64.75 ha |
| 0.5 mi² | 129.5 ha |
| 1 mi² | 259 ha |
| 2 mi² | 518 ha |
| 3 mi² | 777 ha |
| 4 mi² | 1036 ha |
| 5 mi² | 1295 ha |
| 6 mi² | 1554 ha |
| 7 mi² | 1813 ha |
| 8 mi² | 2072 ha |
| 9 mi² | 2331 ha |
| 10 mi² | 2590 ha |
| 12 mi² | 3108 ha |
| 15 mi² | 3885 ha |
| 20 mi² | 5180 ha |
| 25 mi² | 6475 ha |
| 30 mi² | 7770 ha |
| 40 mi² | 10360 ha |
| 50 mi² | 12950 ha |
| 60 mi² | 15540 ha |
| 70 mi² | 18130 ha |
| 75 mi² | 19425 ha |
| 80 mi² | 20720 ha |
| 90 mi² | 23310 ha |
| 100 mi² | 25900 ha |
| 120 mi² | 31080 ha |
| 150 mi² | 38850 ha |
| 200 mi² | 51800 ha |
| 250 mi² | 64750 ha |
| 300 mi² | 77700 ha |
| 400 mi² | 103600 ha |
| 500 mi² | 129499 ha |
| 600 mi² | 155399 ha |
| 750 mi² | 194249 ha |
| 800 mi² | 207199 ha |
| 1000 mi² | 258999 ha |
| 1200 mi² | 310799 ha |
| 1500 mi² | 388498 ha |
| 2000 mi² | 517998 ha |
| 2500 mi² | 647497 ha |
| 3000 mi² | 776996 ha |
| 4000 mi² | 1035995 ha |
| 5000 mi² | 1294994 ha |
| 7500 mi² | 1942491 ha |
| 10000 mi² | 2589988 ha |
| 20000 mi² | 5179976 ha |
| 50000 mi² | 12949941 ha |
| 100000 mi² | 25899881 ha |
| 1000000 mi² | 258998811 ha |
A US survey 'section' is exactly 1 square mile (640 acres). Los Angeles covers about 469 sq mi. In hectares, that gives you: 1 mi² = 258.999 ha, 10 mi² = 2589.99 ha, 100 mi² = 25899.9 ha.
The square mile is the imperial unit for large land areas, standard in US geography and census data. One square mile is exactly 2.589988110336 km² (1.609344 km squared), or 640 acres — the basis of the US Public Land Survey System's square-mile 'sections'. Los Angeles covers about 469 square miles.
The hectare is the metric land unit — exactly 10,000 m², a square 100 meters on each side. It's the standard for farmland, forestry, and land registration in nearly every country outside the US. One hectare is about 2.47 acres. A rugby or soccer pitch is roughly 0.7–1 hectare.