mismatch in local date conversion to utc epoch time and back to date in javascript

Question

let the local date time be local : Mar 10 2014 11:52:50 GMT+0530
converting it to utc epoch time in javascript:

var epochtime=Date.UTC(2014,2,10,11,52,50);

output : 1394452370000

now converting it back to local date:

var utcSeconds =1394452370000;
var d = new Date(0); // The 0 there is the key, which sets the date to the epoch
d.setUTCSeconds(utcSeconds);
alert(d);

output : Fri Jun 09 46158 06:03:20 GMT+0530

but required output is : Mar 10 2014 11:52:50 GMT+0530

please could someone figure out what the problem is ..?

Answer 1

Milliseconds != seconds. You're getting a value in milliseconds, but then using it as seconds.

To turn your value back into a date, simply:

var d = new Date(1394452370000);

Example:

var epochtime=Date.UTC(2014,2,10,11,52,50);
var d = new Date(epochtime);
snippet.log(d.toISOString());

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