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Convert Area from Square Mile to Acre (mi2 to ac)

Single conversion

Square Mile to Acre Conversion Formula

To convert from Square Mile (mi2) to Acre (ac), use the following formula:

 Acre (ac)\textbf{ Acre} \text{ (ac)}

=27878400×143560× Square Mile (mi2)= 27878400 \times \frac{1}{43560}\times \textbf{ Square Mile} \text{ (mi2)}

=640× Square Mile (mi2)= 640\times \textbf{ Square Mile} \text{ (mi2)}

Example

Let's convert 5 Square Mile (mi2) to Acre (ac).

Using the formula:

5×640=32005 \times 640 = 3200

Therefore, 5 Square Mile (mi2) is equal to 32003200 Acre (ac).

What is a Square Mile (mi²)?

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).

Why is London's Financial Center Called the "Square Mile"?

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.

How Do You Convert Square Miles to Other Units?

Converting square miles to other units is essential for comparing land areas globally.

One square mile is equivalent to:

  • 2.59 square kilometers (km²)
  • 640 acres
  • 259 hectares

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.

How is the Square Mile Used in the United States?

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:

  • Land is divided into square townships, each measuring six miles on each side.
  • Each township is then divided into 36 sections.
  • Each section measures exactly one square mile (or 640 acres).

What is an Acre (ac)?

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.

An Acre at a Glance:

  • Size in Square Feet: 43,560 sq ft
  • Size in Yards: 4,840 sq yd
  • Comparison: Covers about 75% of an American football field.
  • Metric Equivalent: About 0.404 hectares.

Where Did the Acre Come From?

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.

What Are the Dimensions of an Acre?

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.

How Does an Acre Compare to a Hectare?

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:

  • 1 hectare = 10,000 square meters
  • 1 hectare = approximately 2.47 acres

What is the imperial system?

The imperial system is a system of measurement that was first defined in the British Weights and Measures Act of 1824. It's known for using units like inches, feet, pounds, and gallons. While most of the world now uses the metric system, the imperial system remains the official system of measurement in the United States and is still used in specific contexts in other countries, such as the United Kingdom and Canada.

Square Mile to Acre Conversion Table

Here are some quick reference conversions from Square Mile (mi2) to Acre (ac):

Square MilesAcres
0.000001 mi20.000640.00064 ac
0.001 mi20.640.64 ac
0.1 mi26464 ac
1 mi2640640 ac
2 mi212801280 ac
3 mi219201920 ac
4 mi225602560 ac
5 mi232003200 ac
6 mi238403840 ac
7 mi244804480 ac
8 mi251205120 ac
9 mi257605760 ac
10 mi264006400 ac
20 mi21280012800 ac
30 mi21920019200 ac
40 mi22560025600 ac
50 mi23200032000 ac
100 mi26400064000 ac
1000 mi2640000640000 ac
10000 mi264000006400000 ac

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