Square Miles to Hectares converter (mi² to ha)
Convert Square Miles (mi²) to Hectares (ha) with this free calculator. Type a value, press Convert, and the page applies the same factor shown in the formula below — no rounded shortcut, and nothing is stored on a server.
Hectares to Square Miles (ha to mi²) ►
How to convert Square Miles to Hectares
1 square mile (mi²) is equal to 258.9988 hectares (ha).
ha = mi² × 258.998811
Multiply the area in square miles by 258.998811:
Example: Convert 2 mi² to ha:
ha = 2 × 258.998811 = 517.998 ha
What is a Square Miles?
The Square Miles (mi²) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
What is a Hectares?
The Hectares (ha) is the starting or target unit on this page. Use the calculator above to convert values without looking up the factor by hand.
This page converts area from Square Miles into Hectares. One mi² equals 258.998811 ha.
Square Miles to Hectares conversion table
Common mi² values and the matching ha result, calculated with the same factor as the widget. Highlight a nearby row if you want a quick check without entering a number.
| Square Miles (mi²) | Hectares (ha) |
|---|---|
| 1 mi² | 258.998811 ha |
| 2 mi² | 517.997622 ha |
| 5 mi² | 1294.994055 ha |
| 10 mi² | 2589.98811 ha |
| 20 mi² | 5179.97622 ha |
| 50 mi² | 12949.94055 ha |
| 100 mi² | 25899.8811 ha |
How this calculator works
The form on this page is a Square Miles-to-Hectares converter. After you enter a number, JavaScript multiplies or rearranges it with the published conversion factor and writes the ha result in the output box. The step-by-step panel repeats the arithmetic so you can copy it into homework or a spreadsheet.
Reviewed by Hamsen, founder of GigaTables and a biology engineer. See the about page for how formulas are checked before a tool is published.
FAQ
How many ha are in 1 mi²?
1 mi² = 258.998811 ha.
How do I convert Square Miles to Hectares?
Multiply the area in square miles by 258.998811:
Is this mi² to ha converter free?
Yes. GigaTables calculators are free to use in a browser. You do not need an account, and the values you type are not uploaded.