Bash: get date and time from another time zone

Question

I would want to get the date and time from another time zone (UTC-4) with a bash command, but I don't want to configure it as the default TZ for the system.
Is there a simple way to do it?
E.g 1 (current):

$ date
fri nov  7 13:15:35 UTC 2014

E.g 2 (what I need):

$ date (+ some option for UTC-4)
fri nov  7 09:15:35 UTC 2014

Darton

Answer 1

You could use

TZ=America/New_York date

or if you want to do date arithmetic you could use

date -d "+5 hours"

Skirr

Thank you @almas shaikh, the first option is the most accurate response for my case. – Darton

But it requires you to know the proper name of the time zone you want, which can be tricky to find out sometimes. You can also use a numeric offset, though it's by no means obvious how. The timezone(3) manual page has the gory details. – Neap

Also maybe check Wikipedia to find e.g. that TZ=Asia/Kolkata is one way to get IST (which is tricky because TZ=UTC-5:30 isn't entirely obvious; e.g. UTC-5.5 doesn't work). – Neap

Any way this could be achieved for macOS? -d argument is for daylight saving offset in the date tool and there is no argument for date string. – Misdemean

Doesn't work on Mac OS. This TZ=UTC date -R does work though. – Ozonize

For time zones with hours and minutes + or - UTC, eg for India: date -d "+5 hours 30 minutes" – Alasteir

Answer 2

You can use offset value in TZ to get the date for a different timezone:

TZ=UTC date -R
Fri, 07 Nov 2014 13:55:07 +0000

TZ=UTC+4 date -R
Fri, 07 Nov 2014 09:54:52 -0400

Dismal

Yes that is how TZ works with offset. I would suggest using offset since it doesn't require you to remember long & valid timezone names. – Dismal

You don't need a subshell. TZ=UTC date sets TZ, runs date, and reverts the value of TZ to its previous value (unset, or different value, or the same value as the one you specified, as the case may be). – Neap

Also, TZ=UTC-4 date confusingly prints the time zone as "UTC" even though it's not. (This is visible in your example output, too.) – Neap

Also better to use date -R for --rfc-2822 format which displays correct offset as well. – Dismal

The TZ=UTC date -R is the only solution I could get to work that works on Mac OS for a redis set key insert I am doing and wanted UTC: redis-cli set starttime "$(TZ=UTC date -R)" – Ozonize

Answer 3

I use a little script for that, so I don't have to know or remember the exact name of the timezone I'm looking for. The script takes a search string as argument, and gives the date and time for any timezone matching the search. I named it wdate.

#!/bin/bash

# Show date and time in other time zones

search=$1

format='%a %F %T %z'
zoneinfo=/usr/share/zoneinfo/posix/

if command -v timedatectl >/dev/null; then
    tzlist=$(timedatectl list-timezones)
else
    tzlist=$(find -L $zoneinfo -type f -printf "%P\n")
fi

grep -i "$search" <<< "$tzlist" \
| while read z
  do
      d=$(TZ=$z date +"$format")
      printf "%-32s %s\n" "$z" "$d"
  done

Example output:

$ wdate fax
America/Halifax                  Fri 2022-03-25 09:59:02 -0300

or

$ wdate canad
Canada/Atlantic                  Fri 2022-03-25 10:00:04 -0300
Canada/Central                   Fri 2022-03-25 08:00:04 -0500
Canada/Eastern                   Fri 2022-03-25 09:00:04 -0400
Canada/Mountain                  Fri 2022-03-25 07:00:04 -0600
Canada/Newfoundland              Fri 2022-03-25 10:30:04 -0230
Canada/Pacific                   Fri 2022-03-25 06:00:04 -0700
Canada/Saskatchewan              Fri 2022-03-25 07:00:04 -0600
Canada/Yukon                     Fri 2022-03-25 06:00:04 -0700

Andrews

I'm getting this error: find: ‘/usr/share/zoneinfo/posix/’: No such file or directory. Maybe because I'm in a Windows 11 machine? – Ashaashamed

Answer 4

If the other solutioons don't work, use

date --date='TZ="UTC+4" 2016-08-22 10:37:44' "+%Y-%m-%d %H:%M:%S"

2016-08-22 16:37:44

Fuel

Answer 5

You may also add minutes using the following for Time Zones with half an hour difference:

date -d "-210 mins"

Celebrated