Distance Between Two Coordinates
Enter two latitude and longitude points to measure the great-circle distance between them in kilometres, miles, and nautical miles. The calculator also returns the initial bearing and the geographic midpoint. Paste decimal degrees, a DMS string, or a Google Maps link — nothing is uploaded, every calculation runs in your browser.
What you can use it for
- Travel & logistics
- Estimate flight distances, plan delivery routes, or work out how far apart two cities really are as the crow flies.
- Aviation & marine
- Read distance in nautical miles and the initial bearing for flight planning, sailing legs, and dead-reckoning checks.
- Field work & GIS
- Measure the gap between two survey points, sensors, or assets without opening a full GIS package.
How the distance is calculated
The tool uses the haversine formula, which computes the shortest distance over the Earth's surface between two points given their latitude and longitude. It treats the Earth as a sphere with a mean radius of 6,371 km. This is the same approach used for "as the crow flies" distances and is accurate to roughly half a percent for almost every practical purpose. Driving or walking distances will be longer because roads rarely follow a straight great-circle path.
Frequently asked questions
- How do I calculate the distance between two coordinates?
- Paste each location into Point A and Point B as decimal degrees (for example 51.5074, -0.1278), a DMS string, or a Google Maps link. The calculator returns the great-circle distance in kilometres, miles, and nautical miles, plus the initial bearing and the midpoint. Everything runs in your browser.
- What is great-circle distance?
- Great-circle distance is the shortest path between two points across the curved surface of the Earth, the same route long-haul aircraft follow. It is more accurate than measuring a straight line on a flat map, which distorts distances especially over long ranges.
- How accurate is the result?
- The tool uses the haversine formula, which models the Earth as a perfect sphere. Compared with the Earth's true ellipsoidal shape this adds an error of up to roughly 0.5% — for example, up to about half a kilometre over a 100 km route, and proportionally less over shorter distances. That is more than accurate enough for travel, logistics, and general use. For survey-grade precision you would need an ellipsoidal model such as Vincenty's formula.
- What is the initial bearing?
- The initial bearing is the compass heading you would start on to travel the great-circle route from Point A to Point B, measured in degrees clockwise from true north. On a curved Earth this heading gradually changes along the route, so it is the starting direction rather than a constant one.
- Can I get the distance in nautical miles?
- Yes. Every result is shown in kilometres, statute miles, and nautical miles at the same time, so it works for road trips, aviation, and marine navigation alike. One nautical mile equals 1.852 km.