JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://maps.google.com/maps/api/js?sensor=false&amp;libraries=geometry"></script>
<p id="distance">Distance: </p>

JavaScript

var p1 = new google.maps.LatLng(6.71532762,80.06215197);
var p2 = new google.maps.LatLng(6.93234287,79.84870747);

var distance = document.getElementById('distance');
distance.innerHTML = distance.innerHTML+calcDistance(p1, p2);

//calculates distance between two points in km's
function calcDistance(p1, p2) {
  return (google.maps.geometry.spherical.computeDistanceBetween(p1, p2) / 1000).toFixed(2);  
}