console.time(timerName) starts a timer that is named by timerName. The timer ends with a call to console.timeEnd(timerName) and the duration will be written into the console window.
<html>
<head>
<meta charset="utf8">
<title>console.time</title>
<script type="text/JavaScript">
var out;
function bar(i) {
console.time('t_bar');
for (var j=0; j < i*3; j++) {
console.log('j=' + j);
}
console.timeEnd('t_bar');
}
function foo() {
console.time('t_foo');
for (var i=0; i<3; i++) {
console.log('i='+i);
bar(i);
}
console.timeEnd('t_foo');
}
function main() {
out = document.getElementById('out');
foo();
}
</script>
</head>
<body onload='main()'>
<div id='out'> </div>
</body>
</html>
