jQuery Detect % Scrolled on Page

jQuery code snippet to create an event action when a user has scrolled down to a percentage of the web page. We have tested that it’s best to use values between 55 and 100% when catching mouse scrolls.


//Example - show a div after 75% of the web page is scrolled.
var webpage = $("body");
var webpage_height = webpage.height();
var trigger_height = webpage_height * 0.75;

if ($(window).scrollTop() > (webpage_height-trigger_height)) {
	//alert($(window).scrollTop()+" > "+(webpage_height-trigger_height));