How many square feet are in 1 square mile?

1 square mile equals 27878400 ft².

How do I convert square feet back to square miles?

Use the reverse converter: 1 square foot equals 3.58701e-8 mi².

Yes. It uses the exact SI/NIST definitions of each unit and shows up to 6 significant digits.

To convert square miles to square feet, multiply the value by 27878400.

ft² = mi² × 27878400

40 mi² × 27878400 = 1115136000 ft²

Square Mile (mi²): Used for large land areas in the US and UK. Equal to 640 acres.
Square Foot (ft²): Used for homes and property in the US and UK. Exactly 0.09290304 square metres.

How do I convert square miles to square feet?: To convert square miles to square feet, multiply the value by 27878400.
How many square feet are in 1 square mile?: 1 square mile equals 27878400 ft².
How many square feet are in 10 square miles?: 10 mi² equals 278784000 ft².
How do I convert square feet back to square miles?: Use the reverse converter: 1 square foot equals 3.58701e-8 mi².
Is this converter accurate?: Yes. It uses the exact SI/NIST definitions of each unit and shows up to 6 significant digits.