How to make JavaScript execute after page load?

These solutions will work:

As mentioned in comments use defer:

<script src="deferMe.js" defer></script>

or

<body onload="script();">

or

document.onload = function ...

or even

window.onload = function ...

Note that the last option is a better way to go since it is unobstrusive and is considered more standard.


Keep in mind that loading the page has more than one stage. BTW, this is pure JavaScript

"DOMContentLoaded"

This event is fired when the initial HTML document has been completely loaded and parsed, without waiting for style sheets, images, and subframes to finish loading. At this stage you could programmatically optimize loading of images and CSS based on user device or bandwidth speed.

Executes after DOM is loaded (before images and CSS):

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

Note: Synchronous JavaScript pauses parsing of the DOM. If you want the DOM to get parsed as fast as possible after the user requested the page, you could turn your JavaScript asynchronous and optimize loading of style sheets

"load"

A very different event, load, should only be used to detect a fully-loaded page. It is an incredibly popular mistake to use load where DOMContentLoaded would be much more appropriate, so be cautious.

Executes after everything is loaded and parsed:

window.addEventListener("load", function(){
    // ....
});

MDN Resources:

https://developer.mozilla.org/en-US/docs/Web/Events/DOMContentLoaded https://developer.mozilla.org/en-US/docs/Web/Events/load

MDN list of all events:

https://developer.mozilla.org/en-US/docs/Web/Events


Reasonably portable, non-framework way of having your script set a function to run at load time:

if(window.attachEvent) {
    window.attachEvent('onload', yourFunctionName);
} else {
    if(window.onload) {
        var curronload = window.onload;
        var newonload = function(evt) {
            curronload(evt);
            yourFunctionName(evt);
        };
        window.onload = newonload;
    } else {
        window.onload = yourFunctionName;
    }
}

You can put a "onload" attribute inside the body

...<body onload="myFunction()">...

Or if you are using jQuery, you can do

$(document).ready(function(){ /*code here*/ }) 

or 

$(window).load(function(){ /*code here*/ })

I hope it answer your question.

Note that the $(window).load will execute after the document is rendered on your page.