Square Kilometers (km²) to Square Miles (mi²) Converter
Enter a value to instantly convert between area units.
1 Square Kilometer = 0.3861 Square Mile
Key Formulas
Acre → Square Foot
ft² = ac × 43560Square Foot → Acre
ac = ft² × 0.0000229568Hectare → Acre
ac = ha × 2.47105Acre → Hectare
ha = ac × 0.404686Formula
mi² = km² × 0.386102158One square kilometer equals 0.386 square miles. US geographers and UK use square miles while much of the world uses km². This conversion is essential for comparing land areas across countries, writing about geographic regions, or working with international datasets. Interestingly, 1 mi² ≈ 2.59 km².
Source: NIST SP 811, Table B.8
Frequently Asked Questions
Real-World Examples
A geographer noting that 1 km² = 0.386 mi² for a textbook on international land comparison.
1 km² = 0.3861 mi²
A regional planner converting 10 km² city area to mi² for a US-Euro comparative study.
10 km² = 3.861 mi²
An environmental scientist calculating 100 km² national park as mi² for international reporting.
100 km² = 38.61 mi²
A demographer converting 1000 km² metropolitan area to mi² for a US news article comparison.
1000 km² = 386.1 mi²