Display date and time:
$ date
Fri Dec 24 14:06:49 JST 2021
To show the time on different timezone, set TZ environment variable:
$ TZ=Australia/Melbourne date
Fri Dec 24 16:06:53 AEDT 2021
Display the date in UTC
$ date -u
Fri Dec 24 05:06:56 UTC 2021
Parse date in your local timezone. This option does NOT work on macOS.
$ date -d '2021-12-24 00:00 UTC'
Fri Dec 24 09:00:00 JST 2021
You can specify timezone here too:
$ TZ=Australia/Melbourne date -d '2021-12-24 00:00 UTC'
Fri Dec 24 11:00:00 AEDT 2021