Convert Square Miles to Square Feet (mi2 to ft2)
1 square mile (mi²) = 27878400 square feet (ft²). 1 ft² = 3.587006428 × 10⁻⁸ mi². Example: 15 mi² = 15 × 27878400 = 418176000 ft².
Also searched as square miles to ft2, square miles in ft2, square miles into square feet, mi2 to ft2, mi2 in square feet, mi2 into square foot, square mile to square foot, mi2 to square feet converter and how many square feet in a square mile.
1 mi² = 27878400 ft²
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk square mile to square foot converter to paste a column from Excel.
How to Convert Square Mile to Square Foot
- 1 mi² = 27878400 ft²
- 1 ft² = 3.587006428 × 10⁻⁸ mi²
- Example: convert 15 mi² to ft²: 15 mi² = 15 × 27878400 ft² = 418176000 ft²
Formula
ft² = mi² × 27878400
Derivation from SI units:
- 1 mi² = (1609.344 m)² = 2 589 988.110336 m² = 640 acres
- 1 ft² = (0.3048 m)² = 0.09290304 m²
- 1 mi² = 2589988.110336 m² ÷ 0.09290304 m² per ft² = 27878400 ft²
Both units are defined exactly, so the factor is exact. Square Mile definition: square mile; Square Foot definition: square foot.
Worked examples
- A reading of 2 mi² converts to 55756800 ft².
2 mi² × 27878400 = 55756800 ft² - A value of 25 mi² is 696960000 ft².
25 mi² × 27878400 = 696960000 ft²
Square Mile to Square Foot conversion table
| Square Miles (mi²) | Square Feet (ft²) |
|---|---|
| 0.1 mi² | 2787840 ft² |
| 0.5 mi² | 13939200 ft² |
| 1 mi² | 27878400 ft² |
| 2 mi² | 55756800 ft² |
| 5 mi² | 139392000 ft² |
| 10 mi² | 278784000 ft² |
| 25 mi² | 696960000 ft² |
| 50 mi² | 1393920000 ft² |
| 100 mi² | 2787840000 ft² |
| 1000 mi² | 27878400000 ft² |
Where it's used
Square Miles are used for US city and county areas, while square feet appear in US floor and building areas. Both measure area, so the conversion is a fixed factor.
Square Mile to other area units
| Conversion | 1 mi² equals |
|---|---|
| square mile to square foot | 27878400 ft² |
| square mile to square meter | 2589988.11 m² |
| square mile to square centimeter | 25899881100 cm² |
| square mile to square inch | 4014489600 in² |
| square mile to hectare | 258.998811 ha |
| square mile to acre | 640 ac |
| square mile to square millimeter | 2589988110000 mm² |
| square mile to square kilometre | 2.58998811 km² |
Show 1 more units
| square mile to square yard | 3097600 yd² |
|---|
Frequently asked questions
How many square feet are in 1 square mile?
1 mi² = 27878400 ft².
How do I convert square miles to square feet?
Multiply the value in mi² by 27878400. For example, 15 mi² × 27878400 = 418176000 ft².
Is the mi² to ft² conversion exact?
Yes. Both units are defined exactly, and 1 mi² is exactly 27878400 ft².
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "square mile (mi²)".
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "square foot (ft²)".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Square Miles to Square Feet (mi2 to ft2). Retrieved October 25, 2026, from https://scientificconverters.com/area/square-miles-to-square-feet/
IEEE
Scientific Converters, "Convert Square Miles to Square Feet (mi2 to ft2)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/area/square-miles-to-square-feet/