Convert Square Mile to Acre

One sq mi equals 640 ac. This converter allows you to easily convert between Square Mile and Acre in real time.

Formula

sq mi × 640 = ac

Example: 1 sq mi = 640 ac

What is Square Mile?

The square mile is a unit of area in the imperial and US customary systems, equal to a square with sides of one mile, or exactly 640 acres. In the United States and United Kingdom, it is used for the areas of counties, states, cities, and other large regions. Manhattan Island in New York City covers about 23 square miles, and the City of London is just 1.12 square miles. Population density figures in English-speaking countries are typically given as persons per square mile.

What is Acre?

The acre is a unit of land area in the imperial and US customary systems, defined as exactly 4,046.8564224 square meters. Its origin is medieval English, where it represented the amount of land a yoke of oxen could plow in one day. In the United States, real estate, farmland, and ranches are commonly measured in acres. One acre is approximately 0.76 of an American football field (excluding end zones). There are 640 acres in a square mile.