Decimal Degrees to Kilometers Calculator

This calculator converts decimal degrees of latitude and longitude into kilometers between two points on Earth. It's useful for geography, navigation, and distance calculations.

How to Use This Calculator

To calculate the distance between two points using decimal degrees:

Enter the latitude and longitude of the first point in decimal degrees
Enter the latitude and longitude of the second point in decimal degrees
Click "Calculate" to see the distance in kilometers
Review the result and use the chart for visualization

The calculator uses the Haversine formula to provide accurate distance measurements between geographic coordinates.

Formula Explained

The distance between two points on Earth's surface can be calculated using the Haversine formula:

a = sin²(Δφ/2) + cos φ1 ⋅ cos φ2 ⋅ sin²(Δλ/2)

c = 2 ⋅ atan2(√a, √(1−a))

d = R ⋅ c

Where:

φ1, λ1 = latitude and longitude of point 1
φ2, λ2 = latitude and longitude of point 2
Δφ = φ2 - φ1
Δλ = λ2 - λ1
R = Earth's radius (6,371 km)

This formula accounts for the Earth's curvature and provides accurate distance measurements between geographic coordinates.

Worked Examples

Example 1: Distance Between Two Points

Calculate the distance between:

Point A: 40.7128° N, 74.0060° W (New York City)
Point B: 34.0522° N, 118.2437° W (Los Angeles)

The calculator would show approximately 3,935 kilometers between these two points.

Example 2: Distance Between Two Close Points

Calculate the distance between:

Point A: 51.5074° N, 0.1278° W (London)
Point B: 51.5154° N, 0.1419° W (near London)

The calculator would show approximately 1.5 kilometers between these two points.

Note: The actual distance may vary slightly due to Earth's curvature and local geography.

Frequently Asked Questions

What is the difference between decimal degrees and degrees, minutes, seconds?: Decimal degrees represent latitude and longitude as single decimal numbers (e.g., 40.7128°). Degrees, minutes, seconds represent them as degrees, minutes, and seconds (e.g., 40°42'46"N). This calculator uses decimal degrees for simplicity.
Why does the Earth's curvature affect distance calculations?: The Earth is not flat, so straight-line distance (as the crow flies) differs from road distance. The Haversine formula accounts for this curvature to provide accurate geographic distances.
Can I use this calculator for air travel distances?: Yes, this calculator provides accurate distances for air travel planning, geography studies, and navigation purposes.
What is the Earth's radius used in this calculation?: The calculator uses the average Earth radius of 6,371 kilometers, which is the most commonly accepted value for such calculations.
How accurate are the results from this calculator?: The results are accurate to within about 0.5% for most practical purposes, as the Haversine formula accounts for Earth's curvature.