What is square kilometre?
A square kilometre is a metric unit of area equal to one million square metres. It is used for measuring large geographic areas such as countries, forests, lakes, and urban zones.
Real-world uses
Square kilometres are used for country areas, city boundaries, national park sizes, and deforestation tracking. Geographic and environmental data, including satellite imagery resolution, reference areas in km². Singapore is about 733 km², for scale.
History
The square kilometre became the standard large-area unit with global metrication, replacing traditional units like the square league. It is the preferred unit for geographic and political area comparisons in international statistics and the United Nations system.
Common mistakes
Thinking 1 km² = 1,000 m². It is actually 1,000,000 m² (1 km × 1 km). Also, confusing square kilometres with kilometres squared in conversation, though mathematically they mean the same thing.
What is square foot?
A square foot is a unit of area in imperial and US customary systems equal to 144 square inches. It is commonly used in the United States for real estate listings, floor plans, and building layouts.
Real-world uses
Square feet are the primary unit for real estate in the United States, Canada, and parts of South Asia. Office space, apartment listings, and retail floor plans are quoted in sq ft. Flooring, tiles, and paint coverage are sold per square foot in these markets.
History
The square foot derives directly from the foot, which has been used since ancient times. It became the de facto real estate standard in the United States and remains deeply entrenched in American property markets despite the global shift toward metric units.
Common mistakes
Forgetting that square footage is an area measure, not a length. A 1,000 sq ft apartment is not 1,000 feet long. Also, nominal tile sizes often include grout spacing, so actual coverage per tile is slightly less than the stated size.
When is this conversion used?
Converting between square kilometre and square foot is common when working across metric and imperial systems, such as international trade, travel between countries with different measurement standards, or following instructions from a different region.
Worked examples
1 square kilometre = 10,763,910.41670972 square foot
1 square foot = 0.09290304 square metre
How to convert square kilometre to square foot
To convert square kilometre to square foot, multiply the value by 10,763,910.41670972.
To convert square foot back to square kilometre, multiply by 9.290304e-08.
Measurement standards
The square metre is the SI derived unit of area. The hectare (10,000 m²) is accepted for use with the SI by the BIPM, particularly for land measurement, though it is not an SI unit itself.
Did you know?
Vatican City, the world's smallest independent state, covers just 0.44 km² (about 109 acres) — smaller than many golf courses. By contrast, Russia spans over 17.1 million km², nearly 39 million times larger.
Quick reference: square kilometre to square foot
| square kilometre | square foot |
|---|---|
| 0.1 | 1,076,391.04167097 |
| 0.5 | 5,381,955.20835486 |
| 1 | 10,763,910.41670972 |
| 2 | 21,527,820.83341944 |
| 5 | 53,819,552.08354861 |
| 10 | 107,639,104.16709721 |
| 25 | 269,097,760.41774303 |
| 50 | 538,195,520.83548605 |
| 100 | 1.076391e+09 |
| 250 | 2.690978e+09 |
| 500 | 5.381955e+09 |
| 1,000 | 1.076391e+10 |
Common values
| square kilometre | square foot | |
|---|---|---|
| A4 paper | 6.200000e-08 square kilometre | 0.66736245 square foot |
| Parking space | 0.0000125 square kilometre | 134.54888021 square foot |
| Tennis court | 0.00026087 square kilometre | 2,807.98131041 square foot |
| Football field (soccer) | 0.00714 square kilometre | 76,854.32037531 square foot |
| Central Park, NYC | 3.41 square kilometre | 36,704,934.52098015 square foot |
Available Area units
More square kilometre conversions
- Convert square kilometre to square metre
- Convert square kilometre to square foot
- Convert square kilometre to square mile
- Convert square kilometre to acre
- Convert square kilometre to hectare
- Convert square kilometre to square centimetre
- Convert square kilometre to square inch
- Convert square kilometre to square yard
- Convert square kilometre to are