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Convert Area from Acre to Square Kilometer (ac to km2)

Single conversion

Acre to Square Kilometer Conversion Formula

To convert from Acre (ac) to Square Kilometer (km2), use the following formula:

 Square Kilometer (km2)\textbf{ Square Kilometer} \text{ (km2)}

=43560×110.7639×1106× Acre (ac)= 43560 \times \frac{1}{10.7639} \times \frac{1}{10^{6}}\times \textbf{ Acre} \text{ (ac)}

=0.0040468603387248116389× Acre (ac)= 0.0040468603387248116389\times \textbf{ Acre} \text{ (ac)}

With 110.7639\frac{1}{10.7639} is the ratio between the base units Square Meter (m2) and Square Foot (ft2).

Example

Let's convert 5 Acre (ac) to Square Kilometer (km2).

Using the formula:

5×0.0040468603387248116389=0.0202343016936240581955 \times 0.0040468603387248116389 = 0.020234301693624058195

Therefore, 5 Acre (ac) is equal to 0.0202343016936240581950.020234301693624058195 Square Kilometer (km2).

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 a Square Kilometer (km²)?

A square kilometer (km²) is a unit used to measure area in the metric system.

It represents a square that is one kilometer long on each side, which equals one million square meters (10⁶ m²).

How Big is a Square Kilometer?

It can be challenging to visualize such a large area, so let's put it into perspective. A single square kilometer is equivalent to:

  • Approximately 247 acres.
  • About 140 international soccer fields.
  • The entire area of a large city park or a small urban neighborhood.

Due to its vast size, the square kilometer is a crucial unit for geographers, urban planners, and scientists when measuring large sections of land or water.

How is the Square Kilometer Used for Global Measurements?

When it comes to measuring our planet, the square kilometer is the standard unit of choice.

The total surface area of Earth is a massive 510 million square kilometers.

This total area is broken down into:

  • Land: Roughly 149 million km² (29.2% of the surface).
  • Water: Roughly 361 million km² (70.8% of the surface).

These figures show why the square kilometer is crucial for scientists studying global climate patterns, mapping population density, and managing natural resources.

How Does a Square Kilometer Compare to a Square Mile?

While much of the world uses the metric system, some countries (like the United States) use the imperial system, where large areas are measured in square miles.

A square kilometer is significantly smaller than a square mile. Here's the quick conversion:

  • 1 square kilometer = approximately 0.386 square miles.
  • 1 square mile = approximately 2.59 square kilometers.

Keeping this difference in mind is essential when comparing geographical data from different countries, whether you're examining the size of a national park or the area of a city.

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.

What is the metric system?

The metric system is a decimal-based system of measurement used by nearly every country in the world. Its key feature is the use of prefixes to denote multiples and submultiples of the base units by powers of ten.

Acre to Square Kilometer Conversion Table

Here are some quick reference conversions from Acre (ac) to Square Kilometer (km2):

AcresSquare Kilometers
0.000001 ac4.0468603387248116389×1094.0468603387248116389\times 10^{-9} km2
0.001 ac0.00000404686033872481163890.0000040468603387248116389 km2
0.1 ac0.000404686033872481163890.00040468603387248116389 km2
1 ac0.00404686033872481163890.0040468603387248116389 km2
2 ac0.00809372067744962327780.0080937206774496232778 km2
3 ac0.0121405810161744349170.012140581016174434917 km2
4 ac0.0161874413548992465560.016187441354899246556 km2
5 ac0.0202343016936240581950.020234301693624058195 km2
6 ac0.0242811620323488698330.024281162032348869833 km2
7 ac0.0283280223710736814720.028328022371073681472 km2
8 ac0.0323748827097984931110.032374882709798493111 km2
9 ac0.036421743048523304750.03642174304852330475 km2
10 ac0.0404686033872481163890.040468603387248116389 km2
20 ac0.0809372067744962327780.080937206774496232778 km2
30 ac0.121405810161744349170.12140581016174434917 km2
40 ac0.161874413548992465560.16187441354899246556 km2
50 ac0.202343016936240581950.20234301693624058195 km2
100 ac0.404686033872481163890.40468603387248116389 km2
1000 ac4.04686033872481163894.0468603387248116389 km2
10000 ac40.46860338724811638940.468603387248116389 km2

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