javascript on page ready code example

Example 1: dom ready js

document.addEventListener("DOMContentLoaded", function() {
  // code
});

Example 2: document ready without jquery

document.addEventListener("DOMContentLoaded", function(event) { 
  //we ready baby
});

Example 3: js on page ready

document.addEventListener("DOMContentLoaded", function(event){
  // your code here
});

Better than 

window.onload = function(){
    // code goes here
};