Windows ISO 8601 timestamp

Question

I need to convert a date in Windows PowerShell to the ISO 8601 format.

In Linux/Unix it was no problem with

TZ=0 date -d "<random-format>" +%Y-%m-%dT%H:%M:%S.000Z

Now I need to do the same in Windows PowerShell. The output format on Windows is

Wednesday, 19. July 2017 01:06:13

How can I do it?

See: https://techontip.wordpress.com/2016/10/10/powershell-tip-date-formatting-iso-8601/. — Andre Kampling, Aug 15 '17 at 08:54
Anyone know why this is not documented here? [Custom date and time format strings](https://learn.microsoft.com/en-us/dotnet/standard/base-types/custom-date-and-time-format-strings) — Gilles Pion, Jul 17 '22 at 10:25

score 57 · Accepted Answer · edited Jan 14 '19 at 05:18

57

PowerShell's Get-Date supports standard .NET time formats. The o round-trip format complies with ISO 8601. Like so,

Get-Date -Format "o"

2017-08-15T12:10:34.4443084+03:00

edited Jan 14 '19 at 05:18

Peter Mortensen

answered Aug 15 '17 at 09:13

vonPryz

Despite of the possible portability problem, I like this solution because it is simple and you can basically memorize it for your quickly-written scripts. – Raúl Salinas-Monteagudo Jan 28 '20 at 11:29

Mathias R. Jessen · Answer 2 · 2021-07-08T13:56:41.437

34

Get-Date supports Unix formatting strings with the -UFormat parameter. You can reuse it:

Get-Date (Get-Date).ToUniversalTime() -UFormat '+%Y-%m-%dT%H:%M:%S.000Z'

edited Jul 08 '21 at 13:56

answered Aug 15 '17 at 10:34

Mathias R. Jessen

1

This should be the correct answer, since the question was framed in a way that suggests _portability is important_. However the implementation in Powershell is incomplete, so formatting elements like `%F` do not work, although `%T` does; nor is there any apparent way to simply specify UTC time like Unix `date` has these days. – Rich Apr 11 '19 at 19:33
1

"%F" works with PowerShell 7: `get-date -UFormat "%F"` produces the expected format. – jgran Aug 06 '20 at 08:15
3

This will give you a timestamp in the local timezone! The "Z" suffix may be incorrect. – cidermole Nov 02 '20 at 16:09
It is incorrect, as I just both did `Get-Date -Format "o"` and `Get-Date -UFormat '+%Y-%m-%dT%H:%M:%S.000Z'` and got the same time, while I live at UTC+3. – Melvin Roest Jul 08 '21 at 13:24
@MelvinRoest In Windows PowerShell or a newer version? I just tried in WPS 5.1 on a machine with UTC+2 and it spits out local time, not universal (answer has been updated) – Mathias R. Jessen Jul 08 '21 at 13:57
I used PowerShell 5.1 – Melvin Roest Jul 08 '21 at 16:50

score 11 · Answer 3 · answered Dec 01 '20 at 23:13

The following works both in Windows PowerShell 5.1 and PowerShell 7.0 on Windows/OS X:

 (Get-Date).ToUniversalTime().ToString("yyyy-MM-ddTHH:mm:ss.fffK")
 
 2020-12-01T22:31:41.402Z

If you don't want your milliseconds, then format string would be "yyyy-MM-ddTHH:mm:ss.000K"

score 9 · Answer 4 · answered May 04 '22 at 10:39

9

Old question but since none of the other answers has it, if you're looking for UTC, this seems to do it:

(Get-Date).ToUniversalTime().ToString("o")

answered May 04 '22 at 10:39

rom99

1

Worth noting that this works all the way back to PowerShell v1. – Frank Lesniak Sep 06 '22 at 03:15

4 Answers4