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Get time zone, daylight saving time, and base offset for any US ZIP code.

ZIP codes are up to date as ofMay 2024.

Ziptz is tested to work with the following versions of Ruby:

• Ruby 3.1.x, 3.2.x, 3.3.x

Add the gem to your Gemfile:

gem 'ziptz'

Starting with version 6.0.0, you'll need to supply your own time zone SQLite database file. You can subscribe to the required dataset here:ZIP Code Time Zones Dataset

First, initialize Ziptz with the path to your time zone database file:

z = Ziptz.new('/path/to/your/tz.db')# or using keyword argumentz = Ziptz.new(db: '/path/to/your/tz.db')

Get the time zone name for any ZIP code:

z.time_zone_name('97213') #=> "America/Los_Angeles"

Get the time zone offset for any ZIP code:

z.time_zone_offset('97213') #=> -28800

Note that offsets do not include daylight saving time.

Determine if the ZIP code uses Daylight Saving Time:

z.time_zone_uses_dst?('97213') #=> true

Get all the zip codes in a time zone:

z.zips('Pacific/Chuuk') #=> ["96942", "96943"]

• America/Adak
• America/Anchorage
• America/Boise
• America/Chicago
• America/Denver
• America/Detroit
• America/Indiana/Indianapolis
• America/Indiana/Knox
• America/Indiana/Marengo
• America/Indiana/Petersburg
• America/Indiana/Tell_City
• America/Indiana/Vevay
• America/Indiana/Vincennes
• America/Indiana/Winamac
• America/Juneau
• America/Kentucky/Louisville
• America/Kentucky/Monticello
• America/Los_Angeles
• America/Menominee
• America/Metlakatla
• America/New_York
• America/Nome
• America/North_Dakota/Beulah
• America/North_Dakota/Center
• America/North_Dakota/New_Salem
• America/Phoenix
• America/Puerto_Rico
• America/Sitka
• America/St_Thomas
• America/Yakutat
• Pacific/Chuuk
• Pacific/Guam
• Pacific/Honolulu
• Pacific/Kosrae
• Pacific/Kwajalein
• Pacific/Majuro
• Pacific/Pago_Pago
• Pacific/Palau
• Pacific/Pohnpei
• Pacific/Saipan
• Pacific/Wake

Note that APO/FPO zip codes will not return a known time zone offset.

If you would prefer raw data instead of a gem, see myZIP Code Time Zones product on AWS Data Exchange to subscribe.

• APO, DPO, and FPO zip codes are no longer included, because they are non-geographic.
• Time zone offsets are now specified in seconds instead of hours.
• Time zone are now more granular. The full list of time zones is:
  • America/Adak
  • America/Anchorage
  • America/Boise
  • America/Chicago
  • America/Denver
  • America/Detroit
  • America/Indiana/Indianapolis
  • America/Indiana/Knox
  • America/Indiana/Marengo
  • America/Indiana/Petersburg
  • America/Indiana/Tell_City
  • America/Indiana/Vevay
  • America/Indiana/Vincennes
  • America/Indiana/Winamac
  • America/Juneau
  • America/Kentucky/Louisville
  • America/Kentucky/Monticello
  • America/Los_Angeles
  • America/Menominee
  • America/Metlakatla
  • America/New_York
  • America/Nome
  • America/North_Dakota/Beulah
  • America/North_Dakota/Center
  • America/North_Dakota/New_Salem
  • America/Phoenix
  • America/Puerto_Rico
  • America/Sitka
  • America/St_Thomas
  • America/Yakutat
  • Pacific/Chuuk
  • Pacific/Guam
  • Pacific/Honolulu
  • Pacific/Kosrae
  • Pacific/Kwajalein
  • Pacific/Majuro
  • Pacific/Pago_Pago
  • Pacific/Palau
  • Pacific/Pohnpei
  • Pacific/Saipan
  • Pacific/Wake

Time zone names now reflect standard tz-database names.

Copyright (c) 2015-2024 Keith Morrison <keithm@infused.org>

Permission is hereby granted, free of charge, to any personobtaining a copy of this software and associated documentationfiles (the "Software"), to deal in the Software withoutrestriction, including without limitation the rights to use,copy, modify, merge, publish, distribute, sublicense, and/or sellcopies of the Software, and to permit persons to whom theSoftware is furnished to do so, subject to the followingconditions:

The above copyright notice and this permission notice shall beincluded in all copies or substantial portions of the Software.

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