# Square mile

For other uses, see Square mile (disambiguation).

The square mile (abbreviated as sq mi and sometimes as mi2)[1] is an imperial and US unit of measure for an area equal to the area of a square of one statute mile.[2] It should not be confused with miles square, which refers to the number of miles on each side squared. For instance, 20 miles square (20 × 20 miles) is equal to 400 square miles; an area of 10 × 40 miles is likewise 400 square miles, but it is not 20 miles square.

One square mile is equal to:

A square mile is equivalent to the following metric system measures:-

When applied to a portion of the earth's surface, which is curved rather than flat, "square mile" is an informal synonym for section.

## References

1. ^ a b Rowlett, Russ (September 1, 2004). "S", How Many? A Dictionary of Units of Measurement. University of North Carolina at Chapel Hill. Retrieved February 22, 2012.
2. ^ Davies, Charles (1872). Mathematical dictionary and cyclopedia of mathematical science. Original from Harvard University: A.S. Barnes and co. p. 582.
3. ^ a b c François Cardarelli (2003). Encyclopaedia of scientific units, weights, and measures: their SI equivalences and origins. Springer. p. 3. ISBN 978-1-85233-682-0. Retrieved 22 February 2012.
4. ^ Zupko, Ronald Edward (1985). A dictionary of weights and measures for the British Isles: the Middle Ages to the twentieth century. American Philosophical Society. p. 353. ISBN 978-0-87169-168-2. Retrieved 22 February 2012.