Convert square miles to acres
Select how many decimal places the result will be rounded to:
How to convert square miles to acres
To convert square miles to acres, multiply a square miles value by 640.
Formula ac = mi² × 640
Example: Convert 5 square miles to acres Calculations: 5 mi² × 640 = 3200 ac
Square mile (mi²)
The square mile is an imperial and US customary systems unit of area, defined as the area of a square with sides of 1 mile. It is approximately equal to 2.59 square kilometers.
Acre (ac)
The acre is an imperial and US customary systems unit of area, defined as the area of a rectangle with sides of 66 and 660 feet. It is approximately equal to 0.4047 hectares.
Browse related converters
Square miles to Square kilometers Square miles to Square meters Square miles to Square yards Square miles to Square feet Square miles to Square inches Square miles to Hectares