Kilometers
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Great-circle distance
Calculate distance from latitude and longitude
Enter decimal-degree coordinates for a start point and an end point. Latitude must be between -90 and 90, and longitude must be between -180 and 180. Commas are accepted and converted safely to decimal points.
Assumptions
Uses the haversine formula with an Earth radius of 6,371.0088 km. Results are rounded for readability and represent straight-line distance, not roads, flights, or terrain-aware routes.
Miles
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Statute miles
Nautical miles
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Useful for marine and aviation planning
Initial bearing
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Forward azimuth from start to end
Midpoint latitude
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Decimal degrees
Midpoint longitude
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Decimal degrees
Copy-friendly summary
Straight-line distance is suitable for rough travel comparison, geography, radio range, and mapping checks. It is not a substitute for road mileage, flight routing, maritime navigation rules, or safety-critical route planning.
How it works
The calculator converts each latitude and longitude value to radians, applies the haversine formula to measure the central angle between both points, and multiplies that angle by Earth’s average radius. This gives the shortest path across the planet’s surface, also called the great-circle distance.
Initial bearing is derived from spherical trigonometry and normalized to a compass heading from 0° to 360°. The midpoint is calculated on the sphere rather than by averaging raw latitude and longitude, which produces better long-distance results.
Rounding is tuned for practical use: distances show two decimal places, midpoint coordinates show five decimal places, and bearing shows one decimal place.
Input tips and common checks
Coordinate format
Use decimal degrees such as 40.7128 or -73.9352. North and east are positive. South and west are negative.
Same-point result
If both points are identical, the distance is 0 and the bearing is shown as not applicable because there is no travel direction.
When numbers look wrong
Check the sign on the longitude first. A missing minus sign will often move a point to the opposite side of the globe.