Square Miles ↔ Square Kilometers Converter

Convert between square miles and square kilometers instantly

Enter square miles to convert to square kilometers
Enter square kilometers to convert to square miles
Conversion Result
1 sq mi = 2.59 km²
1 square mile = 2.58999 square kilometers ā‰ˆ 259 hectares

šŸ“š Square Miles ↔ Square Kilometers Conversion Details

Square Miles to Square Kilometers Formula

km² = sq mi Ɨ 2.58998811

To convert square miles to square kilometers, multiply by approximately 2.58999.

Square Kilometers to Square Miles Formula

sq mi = km² Ɨ 0.38610216

To convert square kilometers to square miles, multiply by approximately 0.3861.

Bidirectional Conversion

This converter works both ways simultaneously:

  • Type in square miles → square kilometers updates automatically
  • Type in square kilometers → square miles updates automatically
  • No buttons to click - works as you type

Common Uses

  • Land area measurement
  • City and country sizes
  • National park areas
  • Real estate and planning

šŸ“ How This Converter Works

This is a bidirectional converter that works in real-time:

  1. Square Miles → Square Kilometers: When you type in the square miles field, the square kilometers field automatically updates
  2. Square Kilometers → Square Miles: When you type in the square kilometers field, the square miles field automatically updates
  3. No swapping needed: Both conversions happen simultaneously
  4. Real-time: Updates happen as you type, no button clicks required
// Conversion Factor:
1 sq mi = 2.58998811 km²
1 km² = 0.38610216 sq mi

// Bidirectional Conversion Logic:
km² = sq mi Ɨ 2.58998811
sq mi = km² Ɨ 0.38610216

// Example 1: Type "10" in square miles
km² = 10 Ɨ 2.58999 = 25.8999

// Example 2: Type "100" in square kilometers
sq mi = 100 Ɨ 0.3861 = 38.61

šŸ“Š Conversion Table

Square Miles Square Kilometers Approximate Size
1 sq mi 2.59 km² ā‰ˆ Central Park, NYC
5 sq mi 12.95 km² ā‰ˆ Small town
50 sq mi 129.5 km² ā‰ˆ Medium city
100 sq mi 259 km² ā‰ˆ Large city
1,000 sq mi 2,590 km² ā‰ˆ Small country
3,796 sq mi 9,833 km² ā‰ˆ Cyprus island

šŸŒ Real-World Examples

New York City: 302.6 sq mi = 783.8 km²
London: 607 sq mi = 1,572 km²
Los Angeles: 468.7 sq mi = 1,214 km²
Singapore: 281.3 sq mi = 728.6 km²

ā“ Frequently Asked Questions

Q: How many square kilometers are in a square mile?

A: There are approximately 2.58999 square kilometers in one square mile.

Q: How does the bidirectional conversion work?

A: Both input fields work simultaneously. When you change the square miles value, square kilometers updates automatically. When you change the square kilometers value, square miles updates automatically.

Q: Do I need to click any button to convert?

A: No! The conversion happens automatically as you type in either field.

Q: How accurate is this converter?

A: This converter provides calculations up to 5 decimal places using the exact conversion factor of 2.58998811.