Calculate geodesic distance accounting for the Earth being an oblate spheroid.
The Earth is not a perfect sphere, so a spherical calculation carries up to about 0.5 per cent error. Ellipsoidal methods such as Vincenty’s reduce that to millimetres at the cost of iteration. For navigation and surveying the spheroidal correction matters; for trip planning the spherical figure is well within tolerance.
Geodesic Distance
Spherical distance, adjustable for the roughly 0.3 per cent flattening of the Earth
Spherical distance, adjustable for the roughly 0.3 per cent flattening of the Earth The Earth is not a perfect sphere, so a spherical calculation carries up to about 0.5 per cent error. Ellipsoidal methods such as Vincenty’s reduce that to millimetres at the cost of iteration.
For navigation and surveying the spheroidal correction matters; for trip planning the spherical figure is well within tolerance.
This calculator takes 4 inputs: First latitude, First longitude, Second latitude, Second longitude. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.