javascript code execution time

Question

I just wanna know,how I can get the execution time of my javascript code.For example I have any javascript code(loop,function etc..) I wanna know how much time takes to executing it.Or test my code how many operations it makes for example per second or minute.

Answer 1

to calculate execution time use console.time (dev tools):

console.time("test");
//execute your code here
console.timeEnd("test");

Answer 2

you can do:

var startFrom = new Date().getTime();
//measured code here
console.log(new Date().getTime() - startFrom);

Answer 3

You should try using a profiling system. If you use Google Chrome, for example, can hit ctrl-shift-i (Windows) or alt-command-i (OS X) and click on the Profiles tab. You can then select the Collect Javascript CPU Profile radio button and then hit start.

You'll find a bit more information here: https://developer.chrome.com/devtools/docs/cpu-profiling

Answer 4

The only thing I know about is Date:

var start = new Date().getTime();  //Time in ms
doSomething();
var end = new Date().getTime();
console.log("Operation took "+(end-start)+" miliseconds.");

But I suppose every browser has it's profiler allowing you to get more info. At least in firefox, there's a profiler if you press Ctrl+Shift+I. I nevr used it, so you must try it yourself.