Great Circle vs Rhumb Line
Pick two airports or click two points on the map and see both classic routes drawn between them: the great circle, which is the genuinely shortest path over the globe, and the rhumb line, which keeps a constant compass bearing and draws as a straight line on a Mercator map. The tool reports the length of each, the distance saved, the initial and final bearings of the great circle, and marks the route’s northern- or southern-most point. Presets cover famous cases like New York–Tokyo, where the shortest path goes near Alaska and the saving is over 1,000 km.
Runs 100% in your browser — your files never leave your device.
Read the full guide to this tool
Notes
- On a sphere the shortest path between two points is an arc of the great circle through them — the curve you see on the map is the map’s distortion, not a detour.
- The rhumb line’s appeal is navigational: one fixed compass course the whole way. Sailors traded distance for simplicity for centuries.
- Distances use the WGS84 mean Earth radius; real flight routes also bend for winds, jet streams and air-traffic corridors, so they rarely match either line exactly.
- Runs 100% in your browser — your files and data never leave your device.
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