Ruby / Rails - Change the timezone of a Time, without changing the value

ruby-on-rails ruby datetime time timezone

Sounds like you want something along the lines of

ActiveSupport::TimeZone.new('America/New_York').local_to_utc(t)

This says convert this local time (using the zone) to utc. If you have Time.zone set then you can of course to

Time.zone.local_to_utc(t)

This won't use the timezone attached to t - it assumes that it's local to the time zone you are converting from.

One edge case to guard against here is DST transitions: the local time you specify may not exist or may be ambiguous.

ruby-on-rails ruby datetime time timezone

I've just faced the same problem and here is what I'm going to do:

t = t.asctime.in_time_zone("America/New_York")

ruby-on-rails ruby datetime time timezone

If you're using Rails, here is another method along the lines of Eric Walsh's answer:

def set_in_timezone(time, zone)  Time.use_zone(zone) { time.to_datetime.change(offset: Time.zone.now.strftime("%z")) }end

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