Square miles to Square kilometres
Type a value in Square miles and get the result in Square kilometres, calculated exactly.
50 Square miles = 129.4994055168 Square kilometres
Precision
Exact factorThis result is exact.
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Formula
km² = mi² × 2.589988110336
To convert Square miles to Square kilometres, multiply the value by 2.589988110336.
Worked examples
- 1 mi² × 2.589988110336 = 2.589988110336 km²
- 50 mi² × 2.589988110336 = 129.4994055168 km²
- 100 mi² × 2.589988110336 = 258.9988110336 km²
This factor is exact by definition.
Conversion table
| Square miles (mi²) | Square kilometres (km²) |
|---|---|
| 1 | 2.589988110336 |
| 2 | 5.179976220672 |
| 3 | 7.769964331008 |
| 4 | 10.359952441344 |
| 5 | 12.94994055168 |
| 6 | 15.539928662016 |
| 7 | 18.129916772352 |
| 8 | 20.719904882688 |
| 9 | 23.309892993024 |
| 10 | 25.89988110336 |
| 15 | 38.84982165504 |
| 20 | 51.79976220672 |
| 25 | 64.7497027584 |
| 30 | 77.69964331008 |
| 40 | 103.59952441344 |
| 50 | 129.4994055168 |
| 60 | 155.39928662016 |
| 70 | 181.29916772352 |
| 75 | 194.2491082752 |
| 80 | 207.19904882688 |
| 90 | 233.09892993024 |
| 100 | 258.9988110336 |
Values marked ≈ are rounded; the rest are exact.
Reverse table: Square kilometres to Square miles
| Square kilometres (km²) | Square miles (mi²) |
|---|---|
| 1 | ≈ 0.3861022 |
| 2 | ≈ 0.7722043 |
| 3 | ≈ 1.158306 |
| 4 | ≈ 1.544409 |
| 5 | ≈ 1.930511 |
| 6 | ≈ 2.316613 |
| 7 | ≈ 2.702715 |
| 8 | ≈ 3.088817 |
| 9 | ≈ 3.474919 |
| 10 | ≈ 3.861022 |
| 15 | ≈ 5.791532 |
| 20 | ≈ 7.722043 |
| 25 | ≈ 9.652554 |
| 30 | ≈ 11.58306 |
| 40 | ≈ 15.44409 |
| 50 | ≈ 19.30511 |
| 60 | ≈ 23.16613 |
| 70 | ≈ 27.02715 |
| 75 | ≈ 28.95766 |
| 80 | ≈ 30.88817 |
| 90 | ≈ 34.74919 |
| 100 | ≈ 38.61022 |
Unit definitions
- Square miles mi²
- Exactly 640 acres, or 2.589988110336 square kilometres.
- Square kilometres km²
- Exactly 1 000 000 square metres, or 100 hectares.
Questions people ask
Square miles to Square kilometres: what is the conversion factor?
One mi² is 2.589988110336 km².
How do I convert Square miles to Square kilometres?
Use the formula above. For example, 50 mi² = 129.4994055168 km².
Is the conversion exact?
Yes. Both units have exact definitions, so the factor is exact; a result is only rounded when its decimals never end.
Factors checked 19 October 2026.