PPolySim OS

Rhumb Line vs Great Circle

Steer a constant compass heading and you follow a rhumb line — simple but longer. Take the shortest path and you follow a great circle — but your heading keeps changing.

Rhumb Line vs Great CircleLive

Controls

Presets

A rhumb line holds a constant compass bearing — easy to steer, and a straight line on a Mercator map, but longer. A great circle is the shortest route but its bearing changes continuously, tracing a curve on the map. Ships and planes crossing oceans follow the great circle, adjusting heading along the way to save fuel and time.

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Data Inspector

Great-circle dist9272 km
Rhumb-line dist11022 km
Extra by rhumb1750 km

Governing equation

Reading this result: Steering the constant-bearing rhumb line adds about 1750 km (18.9%) over the great circle — the penalty grows with higher latitudes and a wider longitude gap.

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How it works

A rhumb line (loxodrome) crosses every meridian at the same angle, appearing as a straight line on a Mercator chart and easy to steer, but it is not the shortest route. A great circle is the shortest path yet curves on the map and demands continuous heading changes. Long-haul ships and aircraft fly great-circle routes, breaking them into rhumb-line segments in practice.

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Frequently asked questions

Is this rhumb line great circle tool really free?▾
Yes. Rhumb Line vs Great Circle runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?▾
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.