Coordinate Distance Calculator
Distance and compass bearing between two coordinates, in metres, kilometres, miles and nautical miles. Paste pairs in decimal degrees, DMS or UTM. Runs in your browser on the WGS84 ellipsoid, with every pair drawn on a map.
Paste the two points
One pair per row: where you measure from, then where you measure to. Paste many rows at once.
| # | From latitude | From longitude | To latitude | To longitude |
|---|---|---|---|---|
| 1 | 24.00252 | 76.023785 | 24.015202 | 76.036883 |
| 2 | ||||
| 3 | ||||
| 4 | ||||
| 5 | ||||
| 6 |
Paste straight from your spreadsheet (Ctrl+V or ⌘V). Drag to select, Ctrl+C or ⌘C copies, Enter moves down, drag the corner square to fill.
What this tool does
Two turbine locations, a substation and a site, a village and the nearest tower: how far apart are they, and in which direction? This calculator takes any number of coordinate pairs and returns the shortest distance over the Earth’s surface between each pair, with the bearing from the first point to the second.
- Paste rows from a spreadsheet: from-point, to-point, one pair per row.
- Distance in metres, kilometres, miles and nautical miles.
- Compass bearing and 16-point direction from the first point, and the back bearing from the second.
- Copy the results back to your spreadsheet, download CSV, or see every pair as a line on the map.
Inputs
Each row holds two points. Latitude and longitude accept decimal degrees, DMS and degrees with decimal minutes in almost any notation; hemisphere can be a sign or a letter. UTM rows take zone, easting and northing.
| Format | Accepted examples |
|---|---|
| Decimal degrees | 24.00252, -79.948862, 33.8688 S, 76.023785E |
| DMS | 24° 00′ 09.072″ N, 24 0 9.072 N, N 24 0 9.072, 24:00:09.072 |
| UTM | Zone set once for all points (43R), or per point: 43R 604131.98 2654884.00 |
Formula and method
Distance
The distance is the geodesic on the WGS84 ellipsoid (a = 6,378,137 m, 1/f = 298.257223563), solved with Vincenty’s inverse formula (1975). The formula iterates on the difference in longitude on the auxiliary sphere until it converges, then evaluates the series for the ellipsoidal arc length. It agrees with GeographicLib to better than a millimetre on every line except nearly antipodal pairs, where it does not converge and the tool falls back to the spherical haversine result.
Bearing
The initial bearing comes from the same solution, atan2(cos U₂ · sin λ, cos U₁ · sin U₂ − sin U₁ · cos U₂ · cos λ), where U₁ and U₂ are the reduced latitudes and λ the converged longitude difference. It is reported as a compass bearing, clockwise from north. The back bearing is the arrival heading turned through 180°, which is the compass direction from the second point back to the first.
Why not the haversine formula?
The haversine formula gives the great-circle distance on a sphere of mean radius 6,371.0088 km. Because the Earth is flattened, it is off by up to 0.5 %, and the error depends on the direction of the line: about 0.3 % long on north to south lines at India’s latitudes and 0.1 % short on east to west lines. For turbine spacing checks, where 5D against 500 m is decided on metres, the ellipsoid is the safer choice.
Worked example
Two wind-turbine locations in Agar Malwa district, Madhya Pradesh: 24.00252, 76.023785 and 24.015202, 76.036883.
| Distance | 1,936.23 m = 1.936 km = 1.203 mi = 1.045 NM |
|---|---|
| Bearing | 43.49° (NE) from the first turbine; back bearing 223.50° |
| Haversine, for comparison | 1,938.72 m, 2.5 m longer than the geodesic |
For a 120 m rotor the pair is 16.1 D apart, well beyond the 7D wake distance. Across the country the difference between the two formulas grows: New Delhi to Mumbai is 1,144.5 km on the ellipsoid and 1,148.1 km on the sphere.
Limitations
- WGS84 only. No datum transformations are applied. Coordinates on Everest 1830 / Kalianpur or another local datum must be transformed first, or the points will be hundreds of metres from where you think they are.
- Surface distance. The result is the length along the ellipsoid, not a straight line through the air or over terrain. Elevation differences and ground slope are ignored.
- Antipodal points. Pairs almost exactly opposite each other on the globe use the spherical formula, which can be off by up to 0.5 % there.
- Input precision. The distance cannot be more precise than the coordinates. Three decimal places of a degree is about 100 m of uncertainty.
- Screening use. This is a calculation utility, not a survey deliverable. Verify results in your GIS before using them in permits or construction drawings.
Frequently asked questions
How is the distance between two coordinates calculated?
On the WGS84 ellipsoid, with Vincenty's inverse formula: the shortest path (geodesic) between the two points on the Earth's flattened shape. It is accurate to about half a millimetre. A simple great-circle formula on a sphere (haversine) can differ from it by up to 0.5 %, which is a few metres per kilometre.
What is the difference between great-circle distance and geodesic distance?
A great circle is the shortest path on a perfect sphere. The Earth is flattened at the poles, so the true shortest path (the geodesic) on the WGS84 ellipsoid is slightly different. This tool reports the geodesic. For two turbines a kilometre apart the two agree to within a few metres; across India they differ by a few kilometres.
What does the bearing mean, and which convention is used?
The bearing is the compass direction from the first point to the second at the start of the path: 0° is north, 90° east, 180° south, 270° west, clockwise. The back bearing is the compass direction from the second point back to the first. Along a long geodesic the heading changes slowly, so the back bearing is not always exactly the bearing plus 180°.
Can I paste many pairs at once?
Yes. Each row is one pair: the first two (or three, for UTM) columns are the starting point and the rest are the destination. Paste straight from a spreadsheet, then copy the results back or download them as CSV. Every row is computed in your browser; nothing is uploaded.
Does it work with UTM coordinates?
Yes. Choose UTM, set the default zone (or give it per row, for example 43R), and enter easting and northing in metres. Each point is converted to latitude and longitude on WGS84 before the geodesic is computed, so two points in different zones are handled correctly.
How precise are the results?
The formula is far more precise than any input you will have. Five decimal places of a degree locate a point to about 1 m; a coordinate given to three decimals is only known to about 100 m, and the distance cannot be better than that.
Is the distance in rotor diameters for turbine spacing?
Not on this page. Divide the distance in metres by the rotor diameter to get it in D; a 5D spacing for a 120 m rotor is 600 m. reneGIS Windmill Micrositing does this for every turbine in a project and checks the wind-wake corridor as well.
Related tools
- Coordinate Converter
Paste a list of coordinates and convert them between decimal degrees, DMS and UTM on WGS84, with zone detection, CSV download and a map.
- UTM Zone Finder
Search a place or drop a pin on the map to get its UTM zone, band, central meridian and EPSG code, with the Indian state it falls in.
- Wind Turbine 5D / 7D Spacing CalculatorComing soon
Turn a rotor diameter into 5D and 7D spacing distances for screening turbine layouts.
- Wind Turbine Distance CheckerComing soon
Check the distance between two turbines in metres and rotor diameters against 5D and 7D thresholds.
Checking turbine spacing across a whole project?
reneGIS Windmill Micrositing measures every turbine against your own layout, competing projects and the constraints around the site, flags 5D and 7D wake conflicts, and exports Excel and Google Earth KML.