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Square Kilometer to Acre Conversion Calculator: Free Online Tool

Convert square kilometers to acres with our free online area converter.

Square Kilometer to Acre Calculator

km²
Square Kilometer
ac
Acre

How to Use the Calculator:

  1. Enter the value you want to convert in the 'From' field (Square Kilometer).
  2. The converted value in Acre will appear automatically in the 'To' field.
  3. Use the dropdown menus to select different units within the Area category.
  4. Click the swap button (⇌) to reverse the conversion direction.

How to Convert Square Kilometer to Acre

Converting Square Kilometer to Acre involves multiplying the value by a specific conversion factor, as shown in the formula below.

Formula:

1 Square Kilometer = 247.1054 acres

Example Calculation:

Convert 10 square kilometers: 10 × 247.1054 = 2471.054 acres

Note: Conversion factors can sometimes be rounded for display purposes. For precise calculations, always use the full factor or rely on the calculator above.

What is a Square Kilometer and a Acre?

The square kilometer (symbol: km²) is a decimal multiple of the SI unit of area, the square meter. It represents the area of a square with sides that are each one kilometer long (1 km² = 1,000,000 m²).

The acre (symbol: ac) is a unit of land area used in the imperial and US customary systems. It is traditionally defined as the area of one chain by one furlong (66 by 660 feet), which is exactly equal to 1/640 of a square mile, 43,560 square feet, or about 4,047 square meters.

Note: The Square Kilometer is part of the metric (SI) system, primarily used globally in science and trade. The Acre belongs to the imperial/US customary system.

History of the Square Kilometer and Acre

As a multiple of the square meter, the square kilometer came into use alongside the metric system for measuring large areas like land masses, cities, and countries. Its adoption followed the establishment of the kilometer as a standard unit of distance.

The acre originated in medieval England as the amount of land tillable by one man behind one ox in one day. Its size varied historically but was standardized under the Weights and Measures Act of 1878 in the UK. It remains a common unit for land measurement in several countries, especially for agricultural and large residential plots.

Common Uses for square kilometers and acres

Explore the typical applications for both Square Kilometer (metric) and Acre (imperial/US) to understand their common contexts.

Common Uses for square kilometers

  • Geography & Cartography: Standard unit for measuring the land area of cities, regions, countries, and continents.
  • Demographics: Used to calculate population density (people per km²).
  • Environmental Science: Measuring the extent of forests, deserts, lakes, or areas affected by environmental changes (e.g., deforestation, wildfires).
  • Urban Planning: Assessing land use and zoning areas within large municipalities.

Common Uses for acres

  • Land Measurement (US/UK etc.): Standard unit for measuring plots of land, especially farms, large residential lots, and undeveloped land in the US, UK, Canada, Australia, India, and other Commonwealth countries.
  • Real Estate: Used in property listings and surveys for land parcels.
  • Agriculture: Common unit for describing farm sizes and field areas.

Frequently Asked Questions

Questions About Square Kilometer (km²)

How many square meters are in a square kilometer?

There are 1,000,000 square meters in one square kilometer (1 km x 1 km = 1000 m x 1000 m).

How many square miles are in a square kilometer?

One square kilometer is approximately 0.3861 square miles.

Is km² used for small areas?

No, it's generally used for very large areas like cities or countries. Square meters, hectares, or acres are used for smaller plots.

Is km² an official SI unit?

While based on the SI unit meter, the official SI derived unit for area is the square meter (m²). However, the square kilometer is a standard metric unit widely accepted for use with SI.

About Acre (ac)

How big is an acre visually?

An acre is roughly 90% of the size of an American football field (including the end zones).

How many square feet are in an acre?

There are exactly 43,560 square feet in one acre.

How many acres are in a hectare?

One hectare contains approximately 2.471 acres.

Is the acre used worldwide?

While common in the US, UK, and Commonwealth countries, it is not part of the metric system (SI) and is less common globally than the hectare or square meter for land measurement.

Conversion Table: Square Kilometer to Acre

Square Kilometer (km²)Acre (ac)
1247.105
51,235.527
102,471.054
256,177.635
5012,355.269
10024,710.538
500123,552.691
1,000247,105.382

All Area Conversions

Square Meter to Square KilometerSquare Meter to Square CentimeterSquare Meter to Square MillimeterSquare Meter to Square InchSquare Meter to Square FootSquare Meter to Square YardSquare Meter to Square MileSquare Meter to AcreSquare Meter to HectareSquare Kilometer to Square MeterSquare Kilometer to Square CentimeterSquare Kilometer to Square MillimeterSquare Kilometer to Square InchSquare Kilometer to Square FootSquare Kilometer to Square YardSquare Kilometer to Square MileSquare Kilometer to HectareSquare Centimeter to Square MeterSquare Centimeter to Square KilometerSquare Centimeter to Square MillimeterSquare Centimeter to Square InchSquare Centimeter to Square FootSquare Centimeter to Square YardSquare Centimeter to Square MileSquare Centimeter to AcreSquare Centimeter to HectareSquare Millimeter to Square MeterSquare Millimeter to Square KilometerSquare Millimeter to Square CentimeterSquare Millimeter to Square InchSquare Millimeter to Square FootSquare Millimeter to Square YardSquare Millimeter to Square MileSquare Millimeter to AcreSquare Millimeter to HectareSquare Inch to Square MeterSquare Inch to Square KilometerSquare Inch to Square CentimeterSquare Inch to Square MillimeterSquare Inch to Square FootSquare Inch to Square YardSquare Inch to Square MileSquare Inch to AcreSquare Inch to HectareSquare Foot to Square MeterSquare Foot to Square KilometerSquare Foot to Square CentimeterSquare Foot to Square MillimeterSquare Foot to Square InchSquare Foot to Square YardSquare Foot to Square MileSquare Foot to AcreSquare Foot to HectareSquare Yard to Square MeterSquare Yard to Square KilometerSquare Yard to Square CentimeterSquare Yard to Square MillimeterSquare Yard to Square InchSquare Yard to Square FootSquare Yard to Square MileSquare Yard to AcreSquare Yard to HectareSquare Mile to Square MeterSquare Mile to Square KilometerSquare Mile to Square CentimeterSquare Mile to Square MillimeterSquare Mile to Square InchSquare Mile to Square FootSquare Mile to Square YardSquare Mile to AcreSquare Mile to HectareAcre to Square MeterAcre to Square KilometerAcre to Square CentimeterAcre to Square MillimeterAcre to Square InchAcre to Square FootAcre to Square YardAcre to Square MileAcre to HectareHectare to Square MeterHectare to Square KilometerHectare to Square CentimeterHectare to Square MillimeterHectare to Square InchHectare to Square FootHectare to Square YardHectare to Square MileHectare to Acre

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