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To convert from Acre (ac) to Square Mile (mi2), use the following formula:
Let's convert 5 Acre (ac) to Square Mile (mi2).
Using the formula:
Therefore, 5 Acre (ac) is equal to Square Mile (mi2).
Here are some quick reference conversions from Acre (ac) to Square Mile (mi2):
| Acres | Square Miles |
|---|---|
| 0.000001 ac | mi2 |
| 0.001 ac | mi2 |
| 0.1 ac | mi2 |
| 1 ac | mi2 |
| 2 ac | mi2 |
| 3 ac | mi2 |
| 4 ac | mi2 |
| 5 ac | mi2 |
| 6 ac | mi2 |
| 7 ac | mi2 |
| 8 ac | mi2 |
| 9 ac | mi2 |
| 10 ac | mi2 |
| 20 ac | mi2 |
| 30 ac | mi2 |
| 40 ac | mi2 |
| 50 ac | mi2 |
| 100 ac | mi2 |
| 1000 ac | mi2 |
| 10000 ac | mi2 |
An acre (ac) is a common unit of area used to measure land in the United States and the United Kingdom.
It is equal to exactly 43,560 square feet.
Because it can be hard to picture that size, this guide breaks down the acre's origins, dimensions, and how it compares to other units.
The acre has deep roots in agriculture. Historically, it was defined as the amount of land that one person with a single ox could plow in one day.
This practical, work-based unit was measured as an area one "furlong" long (660 feet) by one "chain" wide (66 feet).
This origin explains why the acre became a standard for land measurement long before modern units were adopted.
Many people ask about the dimensions of an acre, but because it's a measure of area, it has no required shape or specific length.
While it equals 43,560 square feet, it doesn't have to be a perfect square. An acre can be a long rectangle, an L-shape, or even a circle—as long as the total area adds up.
To help you visualize an acre, imagine a standard American football field, including the end zones. One football field is about 1.32 acres, which means a single acre would cover about three-quarters of it.
While the acre is standard in the US, most of the world uses the hectare, a metric unit of land measurement.
This difference is crucial for anyone working in international real estate, agriculture, or science.
Here's a simple acre to hectare conversion:
A square mile (mi2), with its plural form being square miles, is an imperial unit of area equal to 27,878,400 square feet (ft2).
The "Square Mile" is the famous nickname for the City of London, the historic heart and central financial district of London, England.
This nickname comes from its compact geographical area of just 1.12 square miles (2.90 km2).
Despite its small size, it remains a global hub for finance and business, home to landmarks like the Bank of England and the London Stock Exchange.
Converting square miles to other units is essential for comparing land areas globally.
One square mile is equivalent to:
This is especially useful when comparing data from countries that use the imperial system (like the United States) with those that use the metric system.
In the United States, the square mile is a fundamental unit in the Public Land Survey System (PLSS).
This system, used since 1785 to survey and sell land, is based on a grid. Here's how it works: