Great Circle Calculator

Calculate shortest distance and bearing between two points on a sphere

Calculate Great Circle Distance

Point 1 Coordinates

Range: -90° to +90° (S to N)

Range: -180° to +180° (W to E)

Point 2 Coordinates

Range: -90° to +90° (S to N)

Range: -180° to +180° (W to E)

Calculation Settings

Great Circle Results

8760.10
Distance (kilometers)
Haversine Formula
34.1°
Initial Bearing
NE
8760.10
Spherical Distance (kilometers)
Law of Cosines
131.7°
Final Bearing
SE

Haversine Formula: d = 2r × arcsin(√(sin²(Δφ/2) + cos(φ₁) × cos(φ₂) × sin²(Δλ/2)))

Coordinates: Point 1: (33.9425°, -118.4081°), Point 2: (51.47°, -0.4543°)

Radius: 6371.0 km

Distance Analysis

Formula Comparison: Haversine vs Spherical Law of Cosines
Difference: 0.000 kilometers
✅ Both formulas agree closely - excellent accuracy

Example Calculation

LAX to LHR Flight Route

Los Angeles (LAX): 33.9425°N, 118.4081°W

London Heathrow (LHR): 51.4700°N, 0.4543°W

Great Circle Distance: ~8,760 km (5,440 miles)

Initial Bearing: ~38° (NE)

Why Great Circles Matter

• Airlines use great circle routes to minimize fuel consumption

• Flight paths appear curved on flat maps but are straight in 3D

• Can save hundreds of kilometers compared to straight-line map routes

• Essential for navigation, GPS systems, and satellite communications

Major City Coordinates

New York40.71°N, 74.01°W
London51.51°N, 0.13°W
Tokyo35.68°N, 139.69°E
Sydney33.87°S, 151.21°E
Paris48.86°N, 2.35°E
Cairo30.04°N, 31.24°E

Distance Formulas

📐

Haversine Formula

Most accurate for all distances

🔺

Law of Cosines

Good for short distances

🌐

Vincenty's Formula

Most accurate for ellipsoids

📍

Bearing

Direction from point to point

Understanding Great Circles

What is a Great Circle?

A great circle is the shortest distance between two points on the surface of a sphere. It's formed by the intersection of the sphere with a plane that passes through the center of the sphere. This creates the largest possible circle that can be drawn on the sphere.

Why Do Flight Paths Look Curved?

  • Maps project 3D Earth onto 2D surfaces, causing distortion
  • Great circle routes appear curved on flat maps
  • These "curved" paths are actually straight in 3D space
  • Airlines save fuel by following great circle routes

Mathematical Formulas

Haversine Formula:

d = 2r × arcsin(√(sin²(Δφ/2) + cos(φ₁) × cos(φ₂) × sin²(Δλ/2)))

Initial Bearing:

θ = atan2(sin(Δλ) × cos(φ₂), cos(φ₁) × sin(φ₂) - sin(φ₁) × cos(φ₂) × cos(Δλ))

  • d: Distance between points
  • r: Radius of the sphere
  • φ₁, φ₂: Latitude of point 1 and 2
  • Δφ, Δλ: Difference in latitude and longitude
  • θ: Bearing angle