Short & Snazzy:
+ new Date()
A unary operator like plus triggers the valueOf method in the Date object and it returns the timestamp (without any alteration).
Details:
On almost all current browsers you can use Date.now() to get the UTC timestamp in milliseconds; a notable exception to this is IE8 and earlier (see compatibility table).
You can easily make a shim for this, though:
if (!Date.now) {
Date.now = function() { return new Date().getTime(); }
}
To get the timestamp in seconds, you can use:
Math.floor(Date.now() / 1000)
Or alternatively you could use:
Date.now() / 1000 | 0
Which should be slightly faster, but also less readable.
(also see this answer or this with further explaination to bitwise operators).
I would recommend using Date.now() (with compatibility shim). It’s slightly better because it’s shorter & doesn’t create a new Date object. However, if you don’t want a shim & maximum compatibility, you could use the “old” method to get the timestamp in milliseconds:
new Date().getTime()
Which you can then convert to seconds like this:
Math.round(new Date().getTime()/1000)
And you can also use the valueOf method which we showed above:
new Date().valueOf()
Timestamp in Milliseconds
var timeStampInMs = window.performance && window.performance.now && window.performance.timing && window.performance.timing.navigationStart ? window.performance.now() + window.performance.timing.navigationStart : Date.now(); console.log(timeStampInMs, Date.now());