How can I get the utc offset in Rails?

Question

I need the utc offset from the timezone specified.

score 44 · Answer 1 · answered Aug 05 '14 at 16:31

44

If you need to take daylight savings time into account, you can use something like this:

Time.now.in_time_zone('America/New_York').utc_offset

answered Aug 05 '14 at 16:31

lee

2,351
1
16
18

2

Thank you. This got me the correct offset where `Time.zone.utc_offset` did not. – Henrik N Aug 27 '15 at 12:55
@GregDubicki It's in Rails's `ActiveSupport::TimeWithZone` – Dorian Dec 02 '16 at 18:24
2

This answer works better than `Time.zone.utc_offset`, which inexplicably doesn't account for Daylight Saving Time. – Andrew Smith Sep 08 '20 at 19:11

score 33 · Accepted Answer · edited Aug 26 '12 at 14:45

33

require 'time'

p Time.zone_offset('EST') #=> -18000  #(-5*60*60)

edited Aug 26 '12 at 14:45

KingCrunch

128,817
21
151
173

answered Mar 30 '11 at 15:06

steenslag

79,051
16
138
171

10

Time.zone.utc_offset saved my day =) – Lucas Renan Mar 30 '11 at 17:36
1

Don't forget that in order for this to work properly, you have to set `config.time_zone = 'Berlin'` and `config.active_record.default_timezone = 'Berlin'` in application.rb (in my case, without that it didn't reflect daylight savings adjustments correctly) – Dennis Hackethal Jul 16 '13 at 13:21
1

@Charles, I had to change `config.active_record.default_timezone` to `:local` instead of `'Santiago'`, otherwise every DateTime field change to nil. Is `Time.zone_offset` going to deal with daylight savings correctly? – Sebastialonso Aug 17 '14 at 15:47
1

Lucas' comment to the answer is the best... what steenslag proposes gets borked by daylight savings time if you rely on that offset changing when that happens. (EST vs EDT in this instance). – Wes Johnson Mar 05 '15 at 18:26
`Time.now.utc_offset` also works with DST while `Time.zone.utc_offset` does not. – mb21 Apr 20 '18 at 19:39
Doesn't offset generally depend on a date? – x-yuri Apr 28 '18 at 16:00

score 17 · Answer 3 · answered Sep 17 '19 at 23:32

17

Time.now.in_time_zone('Europe/London').formatted_offset
# => "+01:00"

For a string arguably more usable...

answered Sep 17 '19 at 23:32

colemerrick

1,118
12
17

score 11 · Answer 4 · answered Mar 30 '11 at 15:02

11

my_date_time = DateTime.new(2011, 3, 29, 20)
#=> Tue, 29 Mar 2011 20:00:00 +0000

#will return the same time but with another offset
my_date_time.change(:offset => "+0100")
#=> Tue, 29 Mar 2011 20:00:00 +0100

#will return time for other offset
my_date_time.in_time_zone(-1)
#=>  Tue, 29 Mar 2011 19:00:00 -0100

answered Mar 30 '11 at 15:02

fl00r

82,987
33
217
237

this was what I wanted in the first place, a -N offset! – aldo.roman.nurena Oct 03 '13 at 03:42

score 6 · Answer 5 · answered Jan 22 '16 at 19:25

6

If you are storing a user's timezone as a Time.zone.name string such as 'Eastern Time (US & Canada)' as outlined in http://api.rubyonrails.org/classes/ActiveSupport/TimeZone.html and want to get the timezone offset you can do this:

ActiveSupport::TimeZone.new(user.time_zone).utc_offset / 3600
# => -5

answered Jan 22 '16 at 19:25

timmcliu

1,769
1
13
12

1

Keep in mind, this solution only returns the canonical offset and doesn't contemplate daylight saving time. So, to be safe, is better to use `Time.now.in_time_zone(user.time_zone).utc_offset / 3600` – Alter Lagos Mar 16 '21 at 20:21

score 5 · Answer 6 · answered Dec 02 '16 at 18:15

5

I use Time.zone.utc_offset / 1.hour to get the offset in hours (e.g.: -8 for San Francisco)

answered Dec 02 '16 at 18:15

Dorian

22,759
8
120
116

score 5 · Answer 7 · answered Mar 30 '11 at 14:50

5

If you have a ActiveSupport::TimeWithZone object, you can call time_zone.utc_offset on it. So, for example, Time.zone.now.time_zone.utc_offset.

EDIT: You can also use the gmt_offset instance method on normal Time objects.

answered Mar 30 '11 at 14:50

William

3,511
27
35

score 1 · Answer 8 · answered Sep 18 '12 at 20:32

1

Just to complete the loop here, right now I use:

@course.start.utc_offset/60/60 in order to get the # of hours needed. Jquery countdown needs just -5 or +3 in their timezone argument.

Your welcome google.

answered Sep 18 '12 at 20:32

pjammer

9,489
5
46
56

How can I get the utc offset in Rails?

8 Answers8