Square Metres to Square Kilometres Converter
Convert square metres to square kilometres — divide by a million. Results update as you type; exact factors shown.
One square metre is 0 square kilometres — see the exact factor, not a rounded rule of thumb.
How the square metres to square kilometres converter works
Areas convert through the square metre. Because the inch is exactly 25.4 mm, a square foot is exactly 0.09290304 m², an acre (43,560 square feet) is exactly 4,046.8564224 m² and a square mile (640 acres) is 2,589,988.110336 m². A hectare is 10,000 m² by definition.
The UK is metric for most trade and science but keeps miles, pints, stone and mpg (with the imperial gallon) in daily life.
Common area conversions
| From | To | Units |
|---|---|---|
| 10,000 m² | 0.01 km² | square metres to square kilometres |
| 50,000 m² | 0.05 km² | square metres to square kilometres |
| 100,000 m² | 0.1 km² | square metres to square kilometres |
| 250,000 m² | 0.25 km² | square metres to square kilometres |
| 500,000 m² | 0.5 km² | square metres to square kilometres |
| 1,000,000 m² | 1 km² | square metres to square kilometres |
| 2,000,000 m² | 2 km² | square metres to square kilometres |
| 5,000,000 m² | 5 km² | square metres to square kilometres |
| 10,000,000 m² | 10 km² | square metres to square kilometres |
| 50,000,000 m² | 50 km² | square metres to square kilometres |
| 100,000,000 m² | 100 km² | square metres to square kilometres |
| 1,000,000,000 m² | 1,000 km² | square metres to square kilometres |
Units in this converter and their exact factors
| Unit | Symbol | One unit in square metres |
|---|---|---|
| square millimetre | mm² | 0.000001 square metre |
| square centimetre | cm² | 0.0001 square metre |
| square metre | m² | 1 square metre |
| hectare | ha | 10,000 square metre |
| square kilometre | km² | 1,000,000 square metre |
| square inch | in² | 0.00064516 square metre |
| square foot | ft² | 0.09290304 square metre |
| square yard | yd² | 0.83612736 square metre |
| acre | ac | 4,046.8564224 square metre |
| square mile | mi² | 2,589,988.110336 square metre |
FAQFrequently asked questions about area conversion
How many square metres in a square kilometre?
One million — because a kilometre is a thousand metres, and the square of a thousand is a million.
What is 1,000,000 m²?
Exactly 1 km².
How big is a square kilometre?
100 hectares, or about 247 acres.
Why is the factor a million and not a thousand?
Because area scales with the square of length. This is the most common unit error in area conversion.
What is 10,000 m²?
One hectare, or 0.01 km².
Where these figures come from
- BIPM — The International System of Units (SI Brochure, 9th edition) — definitions of the base and derived units.
- NIST Special Publication 811 — Guide for the Use of the International System of Units — the exact conversion factors used here.
- National Physical Laboratory (NPL) — United Kingdom's national measurement authority.
Last checked: September 2026. Conversion factors are fixed by definition and do not change with tax years or regulations.