Length of a degree of longitude

This formula may be necessary when converting spatial coordinates to earth fixed coordinates. But always it needs a initial point to calculate all coordinates. Formula

Meter as distance of 1 degree longitude 
x = 1 / 1000 * (111.320 * cos(deg2rad(latitude)))

phi    delta LAT    delta LONG
0°     110.574 km    111.320 km
15°    110.649 km    107.551 km
30°    110.852 km    96.486 km
45°    111.132 km    78.847 km
60°    111.412 km    55.800 km
75°    111.618 km    28.902 km
90°    111.694 km    0.000 km

Haversine formula for distance of two coordinates

var R = 6371000; // meters
var φ1 = lat1.toRadians();
var φ2 = lat2.toRadians();
var Δφ = (lat2-lat1).toRadians();
var Δλ = (lon2-lon1).toRadians();

var a = Math.sin(Δφ/2) * Math.sin(Δφ/2) +
        Math.cos(φ1) * Math.cos(φ2) *
        Math.sin(Δλ/2) * Math.sin(Δλ/2);
var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));

var d = R * c;