<!DOCTYPE html>
<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.12.2/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("#btn").click(function(){
$("#box").animate({
width: "400px"
}, {
duration: 5000,
easing: "linear",
step: function(x) {
$("#demo").text(Math.round(x * 100 / 400) + "%");
}
});
});
});
</script>
</head>
<body>
<button id="btn">Start Progress Bar</button>
<div style="border:1px solid green;margin:10px;width:400px;">
<div id="box" style="background:#98bf21;height:50px;width:1px;border:1px solid green;"></div>
</div>
<p id="demo"></p>
</body>
</html>