Calculate bearing

Estimate initial and reverse great-circle bearings, distance, and a 16-point compass direction.

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ToolBearing Calculator
Input
Output
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Preview

How it works

Initial bearing uses a spherical great-circle atan2 formula, and distance uses haversine angular separation multiplied by a 6,371 km Earth radius. Bearing is normalized to 0–360 degrees and mapped to a compass sector.

  • A spherical Earth keeps approximate navigation compact.
  • Reverse bearing is calculated separately because direction changes along a great-circle route.

Worked example

London to Paris
Input
											Start latitude: 51.5074
Start longitude: -0.1278
End latitude: 48.8566
End longitude: 2.3522
Output
												Initial bearing degrees: 148.12
Back bearing degrees: 330.02
Compass point: SSE
Great circle distance km: 343.56

When to use this

Hiking apps estimate waypoint direction, navigation lessons compare return bearings, and maps label route sectors.

Edge cases

  • Identical coordinates have no direction and are rejected.
  • Antimeridian paths need longitude wrapping.
  • Long ellipsoidal routes can differ from the spherical result.