Great Circle Distance Calculator
Enter two points as decimal latitude and longitude to get the straight-over-the-globe distance between them.
Share sends a link that reopens these numbers. Copy details pastes the full breakdown as a list.
The formula
a = sin²(Δφ/2) + cos φ₁ × cos φ₂ × sin²(Δλ/2) distance = 2R × arcsin(√a)
φ is latitude, λ is longitude and R is the Earth’s mean radius, 6,371 km.
What to watch out for
A great circle is the shortest path over a sphere, which is why long flights on a flat map look curved. If your coordinates are in degrees, minutes and seconds, convert them first.
Frequently Asked Questions
How far is London from New York?
From central London (51.5074, −0.1278) to New York (40.7128, −74.0060) is about 5,570 km, or 3,461 miles.
How long is one degree of latitude?
About 111.19 km, or 60 nautical miles. A degree of longitude shrinks towards the poles: at 60° latitude it is 55.60 km.
How do I get the distance across the 180° meridian?
Enter the longitudes as they are, and the shorter way round is used. From 179° E to 179° W on the equator is 222.4 km.