You can use my package here to calculate for you: https://www.npmjs.com/package/haversine-calculator
const haversineCalculator = require('haversine-calculator')
const start = {
latitude: -23.754842,
longitude: -46.676781
}
const end = {
latitude: -23.549588,
longitude: -46.693210
}
console.log(haversineCalculator(start, end))
console.log(haversineCalculator(start, end, {unit: 'meter'}))
console.log(haversineCalculator(start, end, {unit: 'mile'}))
console.log(haversineCalculator(start, end, {threshold: 1}))
console.log(haversineCalculator(start, end, {threshold: 1, unit: 'meter'}))
console.log(haversineCalculator(start, end, {threshold: 1, unit: 'mile'}))
Have a look , I think that this code will be more easily maintainable and flexible than doing it by manually.