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converting time to local timezone not working with moment.js in React

I am converting a timestamp on a DB object using moment:
{moment(comment.created_at).local(true).format('h:mm a')}
My time is outputting in UTC time because that is how it gets created in my DB.
So I am seeing '6:45 PM' for example, when I want to see the time in MY timezone (EST) or the user's relative timezone. According to the moment docs local() will convert to your current timezone? Calling the local() method as shown in my code aboven does not change the time zone. Am I using this incorrectly?
My DB object
{
client_id: 24
created_at: "2022-02-11 17:41:39.330443"
id: 22
report: "sfsf"
report_category: "Client Assigned"
volunteer_id: 23
}

Your database is storing the date without an offset indicator. This means that moment cannot automatically determine the timezone. As per the documentation on parsing dates:
moment(...) is local mode. Ambiguous input (without offset) is assumed to be local time. Unambiguous input (with offset) is adjusted to local time. * moment.utc(...) is utc mode. Ambiguous input is assumed to be UTC.
So if you know your input is UTC and you know it won't have an offset indicator, use moment.utc() instead of moment().
Furthermore, you don't want to use local(true), since passing in "true" will only change the timezone on the object without changing the time (see the documentation). So you're left with:
{moment.utc(comment.created_at).local().format('h:mm a')}

I converted your DB timestamp into ISO format and then passed into your implementation
let t = "2022-02-11 17:41:39.330443"
let utcISOTimestamp = moment.utc(t).toDate()
console.log(utcISOTimestamp)
//let res = moment(utcISOTimestamp).local(true).format('h:mm a');
let res = moment(moment.utc(t).toDate()).local(true).format('h:mm a');
console.log(res)
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>

Try using:
moment.utc('2022-02-11 17:41:39').local().format('YYYY-MM-DD HH:mm:ss')

How to make Moment.js ignore the user's timezone?

I've got a form where I input an event that starts at a certain time. Let's say 9am.
To assign a date/time object I'm using MomentJs. The issue comes when displaying it in different time-zones.
In London will show up 9am as intended - in Kiev will show 11am.
How can I make MomentJS and the browser ignore which timezone is relevant for the user, and just displaying the time I'm giving?
Here's my code:
<p>
Start time:
{moment(event.startDate).format("HH:mm")}
</p>

Assuming you have stored the date as utc (which in this case you probably should have), you could use the following:
moment.utc(event.startDate).format("HH:mm")

Let me provide an alternative answer in Vanilla JavaScript. If you want to make it timezone 'neutral', you can first convert it to UTC using toISOString().
const current = new Date();
const utcCurrent = current.toISOString();
console.log(utcCurrent);
If you want to convert it to a specific timezone, such as London, you can use toLocaleString(). Do take note of the browser support for the timezone though.
const londonTime = new Date().toLocaleString('en-US', { timeZone: 'Europe/London' })
console.log(londonTime);

What you want is a normalized Datetime. This can get a little confusing since the concept of timezones is a rather arbitrary construct.
I like to think of Datetime values as "absolute" and "relative". An "absolute" Datetime is one that is true regardless of which timezone you're in. The most common example of these are UTC(+000) and UNIX Time (also known as Unix epoch, POSIX Time or Unix Timestampe).
UTC is pretty obvious. Its the current time at +000 timezone. UNIX time is a bit more interesting. It represents the number of seconds that have elapsed since January 1, 1970.
You should always store data, in both client and backend, as an "absolute" time. My preference is UNIX time since its represented as a single integer (nice and clean).
moment.js does this for you. When you instantiate your moment object, you can use:
var date = moment.utc(utcString)
or for Unix Time
var date = moment.unix(unixInt)
You can then use this object to display the date in any form you wish:
console.log(date.tz.("America/Toronto"))

The only way I could solve this is by removing the timezone and milliseconds info from the string. I used date-fns lib but I imagine moment will work the same way.
import { format } from 'date-fns'
const myDateTimeString = '2022-02-22T19:55:00.000+01:00'
const dateTimeWithoutTimezone = myDateTimeString.slice(0, 16) // <- 2022-02-22T19:55
format(new Date(dateTimeWithoutTimezone), 'HH:mm')

Using moment.utc() incorrectly converting the date into utc format of "days" format-Moment Javascript

I'm using moment library to convert date into a utc format. here is my date string:
var dateString = "2019-01-31T11:33:16.952+0000";
new Date("2019-01-31T11:33:16.952+0000") // o/p: Thu Jan 31 2019 03:33:16 GMT-0800 (Pacific Standard Time)
since this date is less than a week from today's date, I'm trying to display a text saying "n days ago" instead of actual date. But for some reason I'm getting a future date displayed as "6 days ago" when I do this:
moment.utc("2019-01-31T11:33:16.952+0000").local().fromNow() // shouldnt this display "5 days ago"??
Not sure why moment is not converting the date correctly, any ideas what could be wrong here?

I guess(Considering use of local() converts to your local timezone so time is deducted because you might be in -ve TimeZone) this answer is a solution you're expecting:
Ideally, you would want to pass a UTC timestamp from your server to
the client. That doesn't mean you have to switch your whole server
over to UTC, it just means that you would convert from the time in
your database to UTC on the server before sending it over the web.
Sure, it would be even better if you actually stored times in UTC, but
you said you aren't in a position to make that sort of change right
now. But let's just work off the assumption that you can't change
anything at all on the server.
We'll also assume that your server is fixed to the UTC-07:00 offset.
In real life, this would only be true for places like Arizona that
don't follow daylight saving time. So if you are in Los Angeles and
are in Pacific Time, then some of your data is based on UTC-07:00, but
some of it is based on UTC-08:00. That requires a lot more work if you
want to do it in JavaScript.
Let's also assume that the input is already a string in ISO8601
format. (If it's not, then let me know and I will adjust this code.)
var s = "2013-09-11 18:00:00"; // from action.timeStamp
var actionTime = moment(s + "-07:00", "YYYY-MM-DD HH:mm:ssZ");
var timeAgo = actionTime.fromNow(); The reason your other code didn't
work is because in the first line, you are affected by the time zone
of the browser. The zone setter in the second line just changes the
zone for formatting, not changing the actual moment in time.
Also, when you dump a moment to the console for debugging, make sure
you format it for output. Otherwise you are just looking at its
internal property values, which may or may not make sense directly.

Moment.js - Anywhere in the world, use the same Timezone

I found a couple other posts but they didn't have something specific to what I was looking for.
Here's the scenario:
A user in China (although it could be anywhere in the world) inputs a date time into a field that represents a local time in the U.S. So even though their local machine might be 1:11 AM 02/15/2018 in Beijing, the user is entering a date in Austin, TX for 11:11 AM 02/14/2018 into the date time field.
This is the string I'm pulling from the input field:
'2018-02-14T11:11'
How can I use moment.js to make sure that when I convert '2018-02-14T11:11' to UTC, the UTC string always reflects Austin time, not Beijing time? At the end of the day, we won't know which timezone the user is from, but we will always know the entered timezone will be in Central Standard Time.
What seems to be happening with the below is that when I use these to convert to UTC, the dates are still not reflecting CST, or they are offset incorrectly by several hours.
moment('2018-02-14T11:11').zone("America/Chicago").format()
moment('2018-02-14T11:11').tz("America/Chicago").format()
moment('2018-02-14T11:11', 'CST').tz("America/Chicago").format()
moment('2018-02-14T11:11', "America/Chicago").tz("America/Chicago").format()
To UTC:
moment.utc('2018-02-14T11:11').tz("America/Chicago").toISOString()
I'm definitely missing something. Any advice would be appreciated!
Thanks in advance!

You're close - you will need the Moment-Timezone addon, and then it's like this:
moment.tz('2018-02-14T11:11', "America/Chicago").utc().format()
Let's break that down:
// create the moment with a specific time zone
var m = moment.tz('2018-02-14T11:11', "America/Chicago");
// convert to UTC
m.utc();
// format the output
var s = m.format();

Just add another scenario that I got:
Parse '2018-02-14Z', but ignore 'Z' (UTC), just use local time zone or a specified timezone.
You can simply remove 'Z' from the string or do these:
moment('2018-02-14Z', 'YYYY-MM-DD') will ignore 'Z' or any unmatched characters.
moment.tz('2018-02-14Z', 'YYYY-MM-DD', 'America/Chicago') will use the given timezone.
Of course, you should not do this in the first place. A correct timezone should be used.

Convert hour to date time without adding +1

Hi im using moment js to convert this string 20:00 I tried:
var a = moment("20:00", "HH:mm")
console.log(a.format()) // 2016-09-08T20:00:00+01:00
the problem when I store in mongodb it become
2016-09-10T19:00:00.000Z
I want to store 2016-09-10T20:00:00.000Z
anyway can explain why please ?

When you say that you want to store 2016-09-10T20:00:00.000Z what you are saying is that you want to assume that your date and time is UTC.
To assume that the date you are parsing is a UTC value, use moment.utc
var a = moment.utc("20:00", "HH:mm")
console.log(a.format()) // 2016-09-08T20:00:00Z
Note that when you parse a time without a date, moment assumes the current date. This may not be the behavior that you want.
I'm also not sure if you want a UTC date (which is what you are saying), or a local date without an offset indicator. If you want a local date without an offset indicator, simply use a format without an offset:
moment.utc("20:00", "HH:mm").format('YYYY-MM-DDTHH:mm:ss.SSS')
"2016-09-08T20:00:00.000"
If you are dealing with local dates that do not have a time zone association, I recommend using moment.utc to parse, as this will ensure that the time does not get shifted to account for DST in the current time zone.
For more information about how to parse dates into the time zone or offset that you would like in moment, see my blog post on the subject.

This it how it should look:
var a = moment("20:00", "HH:mm")
console.log(a.utcOffset('+0000').format())
<script src="http://momentjs.com/downloads/moment.min.js"></script>
Doe, the problem is that you are using timezones when you create the date.
MomentJS uses your current timezone automatically.
Mongo however saves the time as it would be in another timezone.
Therefore, if you want the two strings to format the same way, you need to set the timezone.