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javascriptdatetimezoneutc

JavaScript - difference between Date(), new Date(), and ISODate

I've seen various versions of this question, but none of them answer my needs.

I want to create an ISODate for MongoDB and I'm using Node.js.

In Node, when I do:

console.log(Date());

I get:

Mon Sep 26 2016 15:17:04 GMT-0400 (EDT) <-- This is correct.

When I do:

console.log(new Date());

I get:

2016-09-26T19:17:04.731Z <- This is 4 hours ahead

My understanding of the way to do ISODATE is:

var isodate = new Date().toISOString()
console.log(isodate);

Which yields a time 4 hours ahead of "now".

My system date is correct. I run this one different machines, and I get the same results.

Can someone please explain why I'm getting a discrepancy in time?

Solution

  • The difference is that 2016-09-26T19:17:04.731Z related to GMT0 timezone and Mon Sep 26 2016 15:17:04 GMT-0400 (EDT) to your local timezone. Both are point to the same time :)

    You can read more about data formats and timezones in Wiki