Distance Between Coordinates
The Earth is round, so you cannot simply subtract the coordinates. The haversine formula measures the great-circle arc joining the two points, folding the latitude and longitude gaps into half-angle sines so the result holds up near the poles.
Your numbers
Distance (km)
325.11km
Bearing
144.1°
Formula
Distance (km) = 2 × 6371 × asin(√(sin²(ΔStart latitude÷2) + cosStart latitude × cosEnd latitude × sin²(ΔStart longitude÷2)))
This is the direct distance, not the road distance a map app gives. The bearing shown is the direction to face at the start.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Start latitude (°)The starting latitude — positive north, negative south. | 37.5665 | -90 ~ 90 |
| Start longitude (°)The starting longitude — positive east, negative west. | 126.978 | -180 ~ 180 |
| End latitude (°)The end latitude; one degree of latitude is about 111 km anywhere. | 35.1796 | -90 ~ 90 |
| End longitude (°)The end longitude; a degree of longitude shrinks towards the poles. | 129.0756 | -180 ~ 180 |
Step by step
Quick reference table
Results when only Start latitude (°) changes and everything else stays put.
| Start latitude (°) | Distance (km) (km) | Bearing (°) |
|---|---|---|
| 18.8 | 1,833.01 | 6.1 |
| 28.2 | 801 | 13.8 |
| 37.6 | 328.14 | 144.5 |
| 56.3 | 2,353.85 | 175.2 |
| 75.1 | 4,440.34 | 177.3 |
What each result means
| Result | At default values |
|---|---|
| Distance (km) (km)Distance measured in kilometres. | 325.11 |
| Bearing (°)The angle clockwise from north, with north as zero. | 144.1 |
Common mistakes
This is the direct distance, not the road distance a map app gives. The bearing shown is the direction to face at the start.
Glossary
- Start latitude
- The starting latitude — positive north, negative south.
- Start longitude
- The starting longitude — positive east, negative west.
- End latitude
- The end latitude; one degree of latitude is about 111 km anywhere.
- End longitude
- The end longitude; a degree of longitude shrinks towards the poles.
- Distance (km)
- Distance measured in kilometres.
- Bearing
- The angle clockwise from north, with north as zero.
Frequently asked questions
Q. How is Distance Between Coordinates calculated?
Distance (km) = 2 × 6371 × asin(√(sin²(ΔStart latitude÷2) + cosStart latitude × cosEnd latitude × sin²(ΔStart longitude÷2))) — The Earth is round, so you cannot simply subtract the coordinates. The haversine formula measures the great-circle arc joining the two points, folding the latitude and longitude gaps into half-angle sines so the result holds up near the poles.
Q. Can you walk through an example?
With Start latitude 37.5665°, Start longitude 126.978°, End latitude 35.1796°, End longitude 129.0756°, the answer is Distance (km) 325.11km.
Q. What do I need to enter?
Enter Start latitude, Start longitude, End latitude, End longitude. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Start latitude (°) moves the answer to Start latitude (°) 18.8 → Distance (km) (km) 1,833.01 and Start latitude (°) 75.1 → Distance (km) (km) 4,440.34. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
This is the direct distance, not the road distance a map app gives. The bearing shown is the direction to face at the start.
Related calculators
Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.