1 Square km to Square Miles
1 km² ≈ 0.3861 sq mi
1 square kilometer is approximately 0.3861 square miles.
How to convert 1 km² to sq mi
Use the formula sq mi = km² ÷ 2.589988110336:
sq mi = 1 ÷ 2.589988110336sq mi = 0.386102
So 1 km² = 0.386102 sq mi, or about 0.3861 sq mi rounded.
Rounded values and quick estimate
- Rounded to a whole number: 0 sq mi
- Rounded to one decimal place: 0.4 sq mi
- Conversion factor: 1 square kilometer = 0.3861 square miles
Quick mental estimate: multiply by 0.4. For 1 km² that gives about 0.4 sq mi — off by 0.0139 sq mi (3.6%). Use the exact formula when precision matters.
1 Square km in other units
- Square miles
- 0.3861 sq mi
- Square meters
- 1000000 m²
- Square feet
- 10763910.42 sq ft
- Acres
- 247.11 acres
- Hectares
- 100 ha
- Square inches
- 1550003100.01 sq in
- Square centimeters
- 10000000000 cm²
- Square yards
- 1195990.05 sq yd
1 km² and nearby values
| Square kilometers | Square miles |
|---|---|
| 1 km² | 0.3861 sq mi |
| 2 km² | 0.7722 sq mi |
| 3 km² | 1.16 sq mi |
| 4 km² | 1.54 sq mi |
| 5 km² | 1.93 sq mi |
About square kilometers and square miles
A square kilometer is one million square meters, about 0.386 square miles or 247 acres.
A square mile is 640 acres or about 2.59 square kilometers.
Related conversions
Frequently asked questions
What is 1 Square km in Square Miles?
1 square kilometer is about 0.3861 square miles (1 km² ≈ 0.3861 sq mi).
How do you convert 1 km² to sq mi?
Apply sq mi = km² ÷ 2.589988110336: sq mi = 1 ÷ 2.589988110336, sq mi = 0.386102.
How many square kilometers is 0.3861 sq mi?
0.3861 sq mi is about 1 square kilometers.