Square miles to square kilometres
Multiply square miles by 2.59 to get square kilometres.
25 mi² = 64.7497 km²
How to convert square miles to square kilometres
The square kilometre is one million square metres (10⁶ m²). The square mile is exactly 2 589 988.110336 m² (1609.344 m squared).
Worked example — 25 mi²: 25 × 2.59 = 64.7497 km².
Square miles to square kilometres table
| Square miles | Square kilometres |
|---|---|
| 1 mi² | 2.59 km² |
| 2 mi² | 5.18 km² |
| 5 mi² | 12.9499 km² |
| 10 mi² | 25.8999 km² |
| 25 mi² | 64.7497 km² |
| 50 mi² | 129.4994 km² |
| 100 mi² | 258.9988 km² |
| 500 mi² | 1,294.9941 km² |
| 1,000 mi² | 2,589.9881 km² |
Reverse and related
About square miles and square kilometres
Square mile (mi²)
1 mi² = 2.59 km²Definition. Exactly 2 589 988.110336 m² (1609.344 m squared)
History and origin
The square mile is a square one mile on each side, built from the statute mile. It equals about 2.59 square kilometres, or 640 acres.
Current use
Square miles measure land, counties and regions in the United States and United Kingdom.
Source: NIST Handbook 44, Appendix C (area); 1959 yard-and-pound agreement
Square kilometre (km²)
1 km² = 0.386102 mi²Definition. One million square metres (10⁶ m²)
History and origin
The square kilometre is a square one kilometre on each side, one million square metres. It became the metric unit for large land areas.
Current use
Square kilometres measure land area and the size of cities and regions.
Source: BIPM SI Brochure (2019)
Where people use this
Square miles: land and county area. Square kilometres: land area, city and region sizes. 1 sq mi is about 2.59 km².
Every value is carried to full double precision; the display is rounded.
Sources: BIPM SI Brochure (2019); NIST Handbook 44, Appendix C (area); 1959 yard-and-pound agreement.
Questions people ask
How many km² in a square mile?
One square mile is about 2.59 km².
How many km² is 10 sq mi?
10 sq mi is about 25.9 km².
How many acres in a square mile?
One square mile is exactly 640 acres.