Distance Calculator
Find the distance between two points in 2D or 3D space, or the great-circle distance between two latitude/longitude coordinates.
Choose a mode
How to use this calculator
1. Pick the right mode
Use 2D for flat coordinates, 3D when a height or depth (z) matters, and Coordinates for points on the globe given as latitude and longitude.
2. Enter both points
Fill in each coordinate for point 1 and point 2. For map coordinates, use decimal degrees with negative values for south latitudes and west longitudes.
3. Read the distance
The large number is the straight-line distance. In coordinate mode you also get the great-circle distance in both kilometres and miles.
About distance calculations
How are point distances found?
On a plane the distance is √((x₂ − x₁)² + (y₂ − y₁)²), an application of the Pythagorean theorem. In 3D a (z₂ − z₁)² term joins the sum under the root for the straight-line distance.
What is the haversine formula?
For coordinates on a sphere, the haversine formula gives the great-circle (shortest surface) distance. We use an Earth radius of 6371 km and convert to miles with a factor of 0.621371.
Why isn't it exact for real travel?
Great-circle distance assumes a perfect sphere and ignores roads, terrain and the Earth's slight flattening. It is excellent for "as the crow flies" estimates but not driving distance.