What is square mile?
A square mile is a unit of area in imperial and US customary systems equal to 640 acres. It is used to express the size of cities, regions, and geographic territories in the United States and United Kingdom.
Real-world uses
Square miles are used for city areas, county sizes, and population density calculations in the US and UK. Manhattan is about 23 square miles. National parks and wilderness areas are often described in square miles in American contexts.
History
The square mile became a standard geographic unit in English-speaking countries alongside the statute mile. The US Public Land Survey System, established in 1785, divided territory into 36-square-mile townships, each containing 36 one-square-mile sections.
Common mistakes
Assuming 1 square mile = 1 mile × 1 mile = 1 mi². While correct, people forget that 1 sq mi = 640 acres or about 2.59 km², leading to errors when comparing American and metric area figures.
What is square metre?
The square metre is the SI unit of area. It is widely used in real estate, construction, interior design, and land measurement across countries that use the metric system.
Real-world uses
Square metres are the global standard for floor space in real estate listings, construction blueprints, and land surveys outside the US. Solar panel output is rated per square metre, and rental prices in most countries are quoted per m².
History
The square metre is a derived SI unit that follows naturally from the metre. It became the standard area unit as the metric system spread globally. Real estate markets worldwide adopted it as metrication displaced local units like the tsubo (Japan) and pyeong (Korea).
Common mistakes
Confusing linear metres with square metres—a room that is 3 m × 4 m is 12 m², not 7 m. Also, forgetting that when scaling dimensions by a factor, area scales by the square of that factor.
When is this conversion used?
Converting between square mile and square metre 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 mile = 2,589,988.110336 square metre
1 square metre = 1 square metre
How to convert square mile to square metre
To convert square mile to square metre, multiply the value by 2,589,988.110336.
To convert square metre back to square mile, multiply by 3.861022e-07.
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 mile to square metre
| square mile | square metre |
|---|---|
| 0.1 | 258,998.8110336 |
| 0.5 | 1,294,994.055168 |
| 1 | 2,589,988.110336 |
| 2 | 5,179,976.220672 |
| 5 | 12,949,940.55168 |
| 10 | 25,899,881.10336 |
| 25 | 64,749,702.7584 |
| 50 | 129,499,405.5168 |
| 100 | 258,998,811.0336 |
| 250 | 647,497,027.58399999 |
| 500 | 1.294994e+09 |
| 1,000 | 2.589988e+09 |
Common values
| square mile | square metre | |
|---|---|---|
| A4 paper | 2.393833e-08 square mile | 0.062 square metre |
| Parking space | 0.00000483 square mile | 12.5 square metre |
| Tennis court | 0.00010072 square mile | 260.87 square metre |
| Football field (soccer) | 0.00275677 square mile | 7,140 square metre |
| Central Park, NYC | 1.31660836 square mile | 3,410,000 square metre |