# Square Miles to Acres Converter

Enter the area in square miles below to get the value converted to acres.

**Results in Acres:**

Do you want to convert acres to square miles?

## How to Convert Square Miles to Acres

To convert a measurement in square miles to a measurement in acres, multiply the area by the following conversion ratio: 640 acres/square mile.

Since one square mile is equal to 640 acres, you can use this simple formula to convert:

acres = square miles × 640

The area in acres is equal to the area in square miles multiplied by 640.

**For example,**here's how to convert 5 square miles to acres using the formula above.

### How Many Acres Are in a Square Mile?

There are **640** acres in a square mile, which is why we use this value in the formula above.

1 sq mi = 640 ac

Square miles and acres are both units used to measure area. Keep reading to learn more about each unit of measure.

## What Is a Square Mile?

One square mile is equal to the area of a square with sides that are each 1 mile long. One square mile is roughly equal to 2.59 square kilometers or 640 acres.

The square mile is a US customary and imperial unit of area. Square miles can be abbreviated as *sq mi*, and are also sometimes abbreviated as *mi²*. For example, 1 square mile can be written as 1 sq mi or 1 mi².

Learn more about square miles.

## What Is an Acre?

One acre is defined as the area equal to a space that is one chain (66 ft) by one furlong (660 ft), or 10 square chains.^{[1]} That's equal to 43,560 square feet or 1/640 of a square mile for those unfamiliar with those units of measure.

The acre is a US customary and imperial unit of area. Acres can be abbreviated as *ac*; for example, 1 acre can be written as 1 ac.

You can use an acreage calculator to measure the area of a plot of land in acres by locating the boundaries on a map.

Learn more about acres.

## Square Mile to Acre Conversion Table

Square Miles | Acres |
---|---|

1 sq mi | 640 ac |

2 sq mi | 1,280 ac |

3 sq mi | 1,920 ac |

4 sq mi | 2,560 ac |

5 sq mi | 3,200 ac |

6 sq mi | 3,840 ac |

7 sq mi | 4,480 ac |

8 sq mi | 5,120 ac |

9 sq mi | 5,760 ac |

10 sq mi | 6,400 ac |

11 sq mi | 7,040 ac |

12 sq mi | 7,680 ac |

13 sq mi | 8,320 ac |

14 sq mi | 8,960 ac |

15 sq mi | 9,600 ac |

16 sq mi | 10,240 ac |

17 sq mi | 10,880 ac |

18 sq mi | 11,520 ac |

19 sq mi | 12,160 ac |

20 sq mi | 12,800 ac |

21 sq mi | 13,440 ac |

22 sq mi | 14,080 ac |

23 sq mi | 14,720 ac |

24 sq mi | 15,360 ac |

25 sq mi | 16,000 ac |

26 sq mi | 16,640 ac |

27 sq mi | 17,280 ac |

28 sq mi | 17,920 ac |

29 sq mi | 18,560 ac |

30 sq mi | 19,200 ac |

31 sq mi | 19,840 ac |

32 sq mi | 20,480 ac |

33 sq mi | 21,120 ac |

34 sq mi | 21,760 ac |

35 sq mi | 22,400 ac |

36 sq mi | 23,040 ac |

37 sq mi | 23,680 ac |

38 sq mi | 24,320 ac |

39 sq mi | 24,960 ac |

40 sq mi | 25,600 ac |

## References

- National Institute of Standards and Technology, Specifications, Tolerances, and Other Technical Requirements for Weighing and Measuring Devices, Handbook 44 - 2019 Edition, https://nvlpubs.nist.gov/nistpubs/hb/2019/NIST.HB.44-2019.pdf

## More Square Mile & Acre Conversions

- square miles to square yards
- square miles to square feet
- square miles to square inches
- square miles to square kilometers
- square miles to square meters
- square miles to square centimeters
- square miles to square millimeters
- square miles to hectares
- square miles to ares
- square yards to acres
- square feet to acres
- square inches to acres
- square kilometers to acres
- square meters to acres
- square centimeters to acres
- square millimeters to acres
- hectares to acres
- ares to acres