Converting a date time to UTC but keeping the same date and time components

Question

New to JavaScript dates and format and also using moment.js but I have the following date/time:

"2021-08-21 00:00:00"

but need to convert it to be this same date/time using moment.js, but in this format:

"2021-08-21T00:00:00.000Z"

To achieve the top date, I am using the following code:

let value = "00:00:00";
let cdt = moment(value, 'HH:mm:ss');
console.log(cdt.format('YYYY-MM-DD HH:mm:ss'))

Unsure what the .000Z are at the end but can someone pls assist with conversion but keeping to same date and time as first date/time

if you have `"2021-08-21 00:00:00"` i.e. a string - then replace the space with a T, and append a Z - done if you have a Date object, however, adjust the minutes according to the dates timezone `d.setMinutes(d.getMinutes() - d.getTimezoneOffset())` — Bravo, Aug 21 '21 at 08:48
The question doesn't make sense. You say you "have" a timestamp in the format YYYY-MM-DD HH:mm:ss, but then go on to say you're generating that format from a Date using moment.js. Then you want to reformat the string so generated. Why not just format it as you want in the first place? I.e. something like `cdt.format('YYYY-MM-DDTHH:mm:ss.SSSZ')`. The '.000' part is decimal seconds, the Z in a format string is a token that means "show the offset as ±HH:mm", as a character in a timestamp it means +0 offset (aka UTC). Which context are you using it in? — RobG, Aug 22 '21 at 04:32

sbingner · Accepted Answer · 2021-08-21T09:27:38.060

2

This is answered by How do I format a date as ISO 8601 in moment.js?

TLDR; you want moment().toISOString();

EDIT: Since you added your code, you'd probably want:

let value = "00:00:00";
let cdt = moment.utc(value, 'HH:mm:ss');
console.log(cdt.toISOString())

<script src="https://momentjs.com/downloads/moment.min.js"></script>

edited Aug 21 '21 at 09:27

answered Aug 21 '21 at 08:49

sbingner

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Will this still keep the same date and how do I use this based on updated code that I have just added? – ArthurJ Aug 21 '21 at 08:52
Edited it with your code :) hopefully that helps – sbingner Aug 21 '21 at 08:53
it apply the local timezone so not what OP want http://jsfiddle.net/6wmkrfca/ – apple apple Aug 21 '21 at 08:56
By running this code, this changes the whole date value to: `"2021-08-20T14:00:00.000Z"` as I want to keep the original date/time of `2021-08-21 00:00:00` – ArthurJ Aug 21 '21 at 08:56
You need to set the appropriate timezone when you create it then (if you want it unchanged you need to set the timezone you are creating to be Zulu/UTC – sbingner Aug 21 '21 at 08:58
(Edited my answer to have timezone) – sbingner Aug 21 '21 at 09:06
If this is a duplicate, mark it as one, don't answer it. – RobG Aug 21 '21 at 21:40

Bravo · Answer 2 · 2021-08-22T02:44:41.507

0

If I understand what you want ... no need for the no longer updated moment.js library

const dateString = "2021-08-21 00:00:00"

const asLocal = dateString.replace(" ", 'T');

const asUTC = asLocal + 'Z';

console.log(new Date(asLocal).toString());
console.log(new Date(asUTC).toUTCString());

edited Aug 22 '21 at 02:44

answered Aug 21 '21 at 08:51

Bravo

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@RobG - yeah, damn the new IE :p I was actually hoping to find out if I even understand the question to be honest - people say I have this date - but don't say if it's a string or a Date or a the output of something or a general concept! :p – Bravo Aug 22 '21 at 02:40

Converting a date time to UTC but keeping the same date and time components

2 Answers2