Convert Square Miles to Acres

Convert Square Miles (mi²) to Acres (ac) instantly and accurately.

Square Miles (mi²)
Acres (ac)

Conversion Formula

ac = mi² × 640

About Square Miles

A square mile (mi²) is an imperial unit of area equal to a square with sides of one mile (5,280 ft × 5,280 ft). It is used for measuring large land areas like counties, states, and countries in the United States. Los Angeles covers about 503 mi², Rhode Island (smallest US state) is roughly 1,214 mi², and Alaska is about 665,384 mi². This unit is standard in American geography, land surveying, and regional planning.

About Acres

An acre is a traditional unit of land area used primarily in the United States, United Kingdom, and countries with British heritage. One acre equals 43,560 ft² or about 4,047 m². Historically based on the area a yoke of oxen could plow in one day, it remains the standard for measuring agricultural land, residential plots, and rural properties. A football field (without end zones) is roughly 1.32 acres, and most suburban house lots range from 0.25 to 1 acre.

Quick Reference Table

Square Miles (mi²)Acres (ac)
1 mi²640 ac
2 mi²1280 ac
5 mi²3200 ac
10 mi²6400 ac
25 mi²16000 ac
50 mi²32000 ac
100 mi²64000 ac

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