Convert Square Kilometers (km²) to Ares (a)

1 square kilometer equals 10000 ares.

Formula: a = km² × 10000

Square Kilometer to Are Converter

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How to Convert Square Kilometer to Are

1 square kilometer = 10000 ares

Are = Square Kilometer × 10000

Example: 1 km² × 10000 = 10000 a

Reverse Conversion

To convert ares back to square kilometers:

  • Remember, 1 are equals 0.0001 square kilometers.
  • To convert 10000 a to km², multiply 10000 x 0.0001, resulting in 1 km².

Common Square Kilometer to Are Conversions

Square Kilometer to Are (Part 1)
Square Kilometer Are Actions
1 square kilometer 10000 ares
5 square kilometers 50000 ares
10 square kilometers 100000 ares
25 square kilometers 250000 ares
Square Kilometer to Are (Part 2)
Square Kilometer Are Actions
50 square kilometers 500000 ares
100 square kilometers 1000000 ares
500 square kilometers 5000000 ares
1000 square kilometers 10000000 ares

Square kilometers to ares Conversion Table

Reference table with common square kilometers to ares conversions. All values calculated with high precision.

Square Kilometers to Ares Table
0.0001 to 12

Square kilometers Ares Actions
0.0001 km² 1 a
0.00025 km² 2 12 a
0.0005 km² 5 a
0.001 km² 10 a
0.0025 km² 25 a
0.005 km² 50 a
0.01 km² 100 a
0.025 km² 250 a
0.05 km² 500 a
0.1 km² 1000 a
14 km² 2500 a
12 km² 5000 a

Square Kilometers to Ares Table
1 to 100000

Square kilometers Ares Actions
1 km² 10000 a
2 12 km² 25000 a
5 km² 50000 a
10 km² 100000 a
25 km² 250000 a
50 km² 500000 a
100 km² 1000000 a
250 km² 2500000 a
500 km² 5000000 a
1000 km² 10000000 a
2500 km² 2.5 × 107 a
5000 km² 5 × 107 a
10000 km² 1 × 108 a
25000 km² 2.5 × 108 a
50000 km² 5 × 108 a
100000 km² 1 × 109 a

Ares to Square Kilometers Table
1 to 5000

Ares Square kilometers Actions
1 a 0.0001 km²
2 12 a 0.00025 km²
5 a 0.0005 km²
10 a 0.001 km²
25 a 0.0025 km²
50 a 0.005 km²
100 a 0.01 km²
250 a 0.025 km²
500 a 0.05 km²
1000 a 0.1 km²
2500 a 14 km²
5000 a 12 km²

Ares to Square Kilometers Table
10000 to 1 × 109

Ares Square kilometers Actions
10000 a 1 km²
25000 a 2 12 km²
50000 a 5 km²
100000 a 10 km²
250000 a 25 km²
500000 a 50 km²
1000000 a 100 km²
2500000 a 250 km²
5000000 a 500 km²
10000000 a 1000 km²
2.5 × 107 a 2500 km²
5 × 107 a 5000 km²
1 × 108 a 10000 km²
2.5 × 108 a 25000 km²
5 × 108 a 50000 km²
1 × 109 a 100000 km²

Definition of Square Kilometer

Definition

km² — The square kilometer is an SI-derived unit of area equal to exactly 1,000,000 m² (one million square meters). It represents the area of a square with sides of 1 kilometer.

The square kilometer is the standard unit for expressing large geographic areas such as countries, states, cities, lakes, national parks, and ecological regions. It is used globally in geography, cartography, and environmental science.

One square kilometer equals exactly 100 hectares or 10,000 ares. These relationships are exact because all three units are defined as powers of ten of the square meter.

Exact factor
1 km² = 1,000,000 m²
Examples
  • 5,300 km² = 5,300,000,000 m²
  • 5,300 km² = 57,048,725,209 ft²
  • 39 km² = 15.058 mi²

Definition of Are

Definition

a — The are is a metric unit of area equal to exactly 100 square meters. It corresponds to the area of a square with sides of 10 meters.

The are was introduced with the metric system in France and is accepted for use with the SI, though it is not an SI unit itself. It is primarily used in land measurement in parts of Europe and in legal or cadastral contexts.

The symbol a is the internationally recognized abbreviation for the are, as documented by the BIPM. Its decimal multiple, the hectare (ha), is far more common in everyday use.

Exact factor
1 a = 100 m²
Examples
  • 3 a = 300 m²
  • 11 a = 11,840.3 ft²
  • 0.93 a = 1,001.04 ft²

About the Square Kilometer

Facts & Uses

  • 1 km² = 1,000,000 m² exactly = 100 hectares. The metric unit for large geographic areas: cities, countries, lakes, forests.
  • Standard in geography (country and region sizes), environmental science (deforestation, conservation areas), and urban planning.
  • Used in satellite imagery analysis, land use statistics, and population density (people per km²).
  • Reference scales: 1 km² ≈ small village, 100 km² ≈ small town, 1000 km² ≈ large metropolitan core, 1,000,000 km² ≈ medium-sized country.

Curiosities

  • Vatican City is the smallest country at 0.49 km²; Russia is the largest at over 17 million km². Earth's total surface is about 510 million km² (71% ocean).
  • The Amazon rainforest covers approximately 5.5 million km² across nine countries — about the size of the contiguous US west of the Mississippi.
  • Population density extremes: Monaco ~26,000 people/km²; Mongolia ~2 people/km² — a 13,000× difference.
  • Approximate equivalents: 1 km² ≈ 0.386 mi² ≈ 247 acres ≈ 100 hectares.

Sources

Frequently Asked Questions

How many ares are in one square kilometer?

One square kilometer equals 10000 ares. To convert, multiply the square kilometer value by 10000. For the reverse, divide the are value by 10000 (or multiply by 0.0001).

What is 10 square kilometers in ares?

10 square kilometers = 100000 ares. This is one of the most commonly searched conversions for this pair.

How precise is the square kilometer-to-are conversion?

The factor 10000 is accurate to 6 significant figures, derived from international measurement standards. Our calculator uses full precision internally.

Looking for the reverse? Convert Are to Square Kilometer

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Conversion factors verified against NIST, BIPM, ISO 80000-3 Derived from SI base units (m², BIPM). Last reviewed: March 2026
Adilson Fernandes By Adilson Fernandes
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All unit conversions on CoolConversion use conversion factors defined or documented by internationally recognised standards bodies (such as ISO and NIST), including both SI and non-SI units.