Square Miles Conversion

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Square Miles



sq mi

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Wordwide use:

Square miles is a widely used unit of measurement for land area across the globe. It is primarily used in countries that have adopted the imperial system of measurement, such as the United States, United Kingdom, and Canada. In these countries, square miles are commonly used to measure large areas of land, such as states, provinces, and national parks. The United States, in particular, heavily relies on square miles as a unit of measurement due to its vast size and diverse geography. It is used to measure everything from the size of individual states to the total land area of the entire country.


A square mile (mi²) is defined as the area of a square with sides measuring one mile in length. One square mile is equivalent to 640 acres or approximately 2.59 square kilometers.


The origin of the square mile as a unit of measurement can be traced back to ancient times. The concept of measuring land area has been important for various purposes, such as agriculture, taxation, and military planning. However, the specific term "square mile" emerged during the medieval period in England.

The term "mile" itself has its roots in the Roman Empire, where it was used to measure distances along roads. The Roman mile was defined as 1,000 paces, which roughly equated to 1,480 meters. This measurement was later adopted by the Anglo-Saxons and became known as the statute mile. The square mile, as we know it today, is simply the area of a square with sides measuring one mile in length. It gained prominence in England during the reign of Queen Elizabeth I in the 16th century. The square mile was used to measure the area of land owned by the City of London, which became known as the "Square Mile" or the "City."

Usage context:

Square miles is a commonly used unit of measurement in various contexts, primarily in countries that follow the imperial system. It is particularly useful when measuring large areas of land, such as national parks, states, or countries. Square miles are often used in geographical and environmental studies to quantify the size of regions, as well as to compare and analyze different land masses.