javascript getMonth() off by 2?-CodePudding

I understand that getMonth() is zero indexed so, for example, June is 5. But I'm getting that it's 'off' by 2 in some situations.

myDate = new Date(1622513190000)
month = myDate.getMonth()

console.log(myDate)
console.log(month)

Returns:

2021-06-01T02:06:30.000Z

4

Anyone have an idea why this is returning 4 and not 5? I'm using node v14.15.5 and am getting the expected result for other dates (September is 8, August is 7)

Thanks!

CodePudding user response：

Hi and welcome here :)

Working with dates and timezone is a bit tricky, everyone here can attest it. For general information, I suggest you to read this article about Coordinated universal time.

The Z you can see in myDate value means Zulu time, military name for UTC±00:00, the reference timezone. ±00:00 represents an eventual offset with the Zulu time.

After having gone crazy about this question, I advice you to :

always get and store dates in Zulu format, and then compute time lapse with them
you can show users local dates, but it's only to display them. If you have to compute with a user input, first get the UTC equivalent (as @RobG advised).

Good luck ! :)