geo-distance estimate with Haversine formula

Haversine formula - Wikipedia

The haversine formula determines the great-circle distance between two points on a sphere given their longitudes and latitudes. Important in navigation, it is a special case of a more general formula in spherical trigonometry, the law of haversines, that relates the sides and angles of spherical triangles.

in Javascript

const earthRadius = 6378137

const toRad = value => (value * Math.PI) / 180

const robustAcos = value => value > 1 ? 1 : value < -1 ? -1 : value

// Calculates the distance between two points, in meters

// lat(itute) range: -90 to 90; > 0 North, < 0 South of equator

// lon(gitude) range: -180 to 180; < 0 West, > 0 East of Greenwich, UK

export const geoDistance = ( fromLat, fromLon, toLat, toLon, accuracy = 1 ) => {

    const distance =

        Math.acos(

            robustAcos(

                Math.sin(toRad(toLat)) * Math.sin(toRad(fromLat)) +

                    Math.cos(toRad(toLat)) *

                        Math.cos(toRad(fromLat)) *

                        Math.cos(toRad(fromLon) - toRad(toLon))

            )

        ) * earthRadius;

    return Math.round(distance / accuracy) * accuracy;

};

based on

geolib - npm

Library to provide basic geospatial operations like distance calculation, conversion of decimal coordinates to sexagesimal and vice versa, etc. This library is currently 2D, meaning that altitude/elevation is not yet supported by any of its functions!

Weekly Downloads 170K, Last publish 3 months ago, MIT license

manuelbieh/geolib: Zero dependency library to provide some basic geo functions @GitHub

haversine-distance - npm

Haversine formula in Javascript. In meters. Nothing more.

MIT, 31K down, updated 3 years ago

both provide same results