●时间戳(timestamp)定义

时间戳指的是从格林威治时间1970年01月01日00时00分00秒起至现在的总秒数。严格来说，不管你处在地球上的哪个地方，任意时间点的时间戳都是相同的。这点有利于线上和客户端分布式应用统一追踪时间信息。时间戳是没有时区概念的，同一个时间戳对不同时区显示的时间不一样而已。

最近在做一个api的自测时发现，在不同环境同一个api返回的response里的时间戳结果不太一样。查看了下编程逻辑，代码如下：

SimpleDateFormat sDateFormat = new SimpleDateFormat("yyyy-MM-dd");

Date date=sDateFormat.parse(m.getDaytime());//格式类似"2020-02-20"

getEventNumDateResponse.setTime(date.getTime());

sDateFormat= null;

这段代码逻辑上没什么问题，但在不同环境上运行结果不一样，问题出在哪了？

细想，怀疑Date与时区肯定有关系，经过检查，发现本地的时区是默认的东八区UTC+0800，本地java 程序运行也没配置时区，采用的自然是系统时区东八区，而在另外一个开发环境，jar包运行时配置了-Duser.timezone=UTC，虽然系统默认也是东八区，原来是这个设置导致的。

比如"2020-02-20"这个字符串时间，被SimpleDateFormat parse后，如果当前的运行时区(没设置则是系统时区)是UTC+0800，则时间Date是：Thu Feb 20 00:00:00 CST 2020

CST时区包含了UTC+8:00 也就是这个时间自然是东八区的 2020-02-20 00:00:00 这个时间，对应着是UTC 0时区的2020-02-19 16:00:00时间，通过getTime获取的时间戳是：

System.out.println(TimeZone.getDefault().getRawOffset());

28800000

System.out.println(sdf.parse("2020-02-20").getTime());

1582128000000

通过在pg里转化验证：

SELECT TO_TIMESTAMP(1582128000)AT TIME ZONE 'UTC-0' ;

2020-02-19 16:00:00

SELECT TO_TIMESTAMP(1582128000)AT TIME ZONE 'Asia/Shanghai' ;

2020-02-20 00:00:00

同样，当我们在系统里设置了时区为UTC 0时区，或者在jar运行时设置了-Duser.timezone=UTC，或者在代码里配置了

TimeZone.setDefault(TimeZone.getTimeZone("UTC"));

这样，当后面SimpleDateFormat parse后， 则时间Date是：Thu Feb 20 00:00:00 UTC 2020，表明是UTC 0时区的 2020-02-20 00:00:00 这个时间，对应着是UTC+8时区的

2020-02-20 08:00:00时间，通过getTime获取的时间戳是：

System.out.println(TimeZone.getDefault().getRawOffset());

0

System.out.println(sdf.parse("2020-02-20").getTime());1582156800000

通过在pg里转化验证：

SELECT TO_TIMESTAMP(1582156800)AT TIME ZONE 'UTC-0';2020-02-20 00:00:00

----直接写时区偏移(基于格林威治时区，是反的，即提前-滞后+，例如正常东八区，需要写-8:00，因此建议直接用时区缩写，见后面附表，当然也可以写

---Asia/Shanghai表示东八区

SELECT TO_TIMESTAMP(1582156800)AT TIME ZONE 'Asia/Shanghai' ;2020-02-20 08:00:00

写到这里，相信大家都明白了为啥同一个程序在不同机器上跑出的涉及时间戳的结果不一致，这一点要注意额，千万别掉坑里。

最后，说一下涉及时间戳时，配置时区的几种方式：

Linux中：(以redhat 7.0为例)

查看：

[root@localhost Desktop]#timedatectl status

Local time: Thu 2020-02-27 14:57:58CST

Universal time: Thu2020-02-27 06:57:58UTC

RTC time: Thu2020-02-27 06:58:00Time zone: Asia/Shanghai (CST, +0800)

NTP enabled: yes

NTP synchronized: no

RTCinlocal TZ: no

DST active: n/a

或者：

[root@localhost Desktop]# date -R

Thu, 27 Feb 2020 15:00:25 +0800

设置：

# timedatectl set-timezone "Asia/Shanghai"

在Java中也可以设置时区

1)启动设置

java -Duser.timezone=Asia/Shanghai -jar xxx.jar

2) 代码中设置

TimeZone.setDefault(TimeZone.getTimeZone("UTC"));

SimpleDateFormat sdf= new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println(sdf.parse("2018-09-01 08:00:00").getTime());

3) 单次处理生效，建议使用joda的时间包

joda-time

joda-time

2.9.9

DateTimeFormatter dateTimeFormatter= DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss").withChronology(ISOChronology.getInstance(DateTimeZone.forID("Asia/Shanghai")));

System.out.println(dateTimeFormatter.parseDateTime("2018-09-01 08:00:00").getMillis());

另外，了解Java8 的朋友可能都知道，Java8提供了一套新的时间处理API，这套API比以前的时间处理API要友好的多。

Java8 中加入了对时区的支持，带时区的时间为分别为：ZonedDate、ZonedTime、ZonedDateTime。其中每个时区都对应着 ID，地区ID都为 “{区域}/{城市}”的格式，如Asia/Shanghai、America/Los_Angeles等。

Java中的Date类中是不包含时区信息的，在使用System.out.println打印Date的时候，回调用Date.toString方法，该方法会获取系统的默认时区来转换时间。

在Java8中可以使用ZonedTime、ZonedDate和ZonedDateTime来表示带有时区信息的时间。

LocalDateTime now = LocalDateTime.now(ZoneId.of("America/Los_Angeles"));

System.out.println(now);//获取秒数

Long second = LocalDateTime.now().toEpochSecond(ZoneOffset.of("+8"));//获取毫秒数

Long milliSecond = LocalDateTime.now().toInstant(ZoneOffset.of("+8")).toEpochMilli();

//时间转字符串格式化

DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmssSSS");

String dateTime = LocalDateTime.now(ZoneOffset.of("+8")).format(formatter);

//字符串转时间

String dateTimeStr = "2018-07-28 14:11:15";

DateTimeFormatter df = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

附几种时区标准：

1.UTC

UTC＋时区差＝本地时间

时区差东为正，西为负

UTC是协调世界时(Universal Time Coordinated)英文缩写，是由国际无线电咨询委员会规定和推荐,并由国际时间局(BIH)负责保持的以秒为基础的时间标度。UTC相当于本初子午线(即经度0度)上的平均太阳时，过去曾用格林威治平均时(GMT)来表示.北京时间比UTC时间早8小时，以1999年1月1日0000UTC为例，UTC时间是零点，北京时间为1999年1月1日早上8点整。

2.GMT(Greenwich Mean Time)是格林尼治平时：

由于地球轨道并非圆形，其运行速度又随着地球与太阳的距离改变而出现变化，因此视太阳时欠缺均匀性。视太阳日的长度同时亦受到地球自转轴相对轨道面的倾斜度所影响。为着要纠正上述的不均匀性，天文学家计算地球非圆形轨迹与极轴倾斜对视太阳时的效应。平太阳时就是指经修订后的视太阳时。在格林尼治子午线上的平太阳时称为世界时(UT0)，又叫格林尼治平时(GMT)。 为了确保协调世界时与世界时(UT1)相差不会超过0.9秒，有需要时便会在协调世界时内加上正或负闰秒。因此协调世界时与国际原子时(TAI)之间会出现若干整数秒的差别。位于巴黎的国际地球自转事务中央局(IERS)负责决定何时加入闰秒。

也就是说，UTC 基本上等于GMT

3.CET

(英語：Central European Time，CET)欧洲中部时间是比世界标准时间(UTC)早一个小时的时区名称之一。它被大部分欧洲国家和部分北非国家采用。冬季时间为UTC+1，夏季欧洲夏令时为UTC+2。

4.CEST

欧洲中部夏令时间(Central European Summer Time，简称CEST)比世界标准时间(UTC)早两个小时的时区名称之一。它被大部分欧洲国家和部分北非国家在夏天采用(UTC+2)，冬季这些国家使用欧洲中部时间(UTC+1)

附JAVA TIMEZONE 时区表：

Etc/GMT+12

Etc/GMT+11

MIT

Pacific/Apia

Pacific/Midway

Pacific/Niue

Pacific/Pago_Pago

Pacific/Samoa

US/Samoa

America/Adak

America/Atka

Etc/GMT+10

HST

Pacific/Fakaofo

Pacific/Honolulu

Pacific/Johnston

Pacific/Rarotonga

Pacific/Tahiti

SystemV/HST10

US/Aleutian

US/Hawaii

Pacific/Marquesas

AST

America/Anchorage

America/Juneau

America/Nome

America/Yakutat

Etc/GMT+9

Pacific/Gambier

SystemV/YST9

SystemV/YST9YDT

US/Alaska

America/Dawson

America/Ensenada

America/Los_Angeles

America/Tijuana

America/Vancouver

America/Whitehorse

Canada/Pacific

Canada/Yukon

Etc/GMT+8

Mexico/BajaNorte

PST

PST8PDT

Pacific/Pitcairn

SystemV/PST8

SystemV/PST8PDT

US/Pacific

US/Pacific-New

America/Boise

America/Cambridge_Bay

America/Chihuahua

America/Dawson_Creek

America/Denver

America/Edmonton

America/Hermosillo

America/Inuvik

America/Mazatlan

America/Phoenix

America/Shiprock

America/Yellowknife

Canada/Mountain

Etc/GMT+7

MST

MST7MDT

Mexico/BajaSur

Navajo

PNT

SystemV/MST7

SystemV/MST7MDT

US/Arizona

US/Mountain

America/Belize

America/Cancun

America/Chicago

America/Costa_Rica

America/El_Salvador

America/Guatemala

America/Indiana/Knox

America/Indiana/Tell_City

America/Knox_IN

America/Managua

America/Menominee

America/Merida

America/Mexico_City

America/Monterrey

America/North_Dakota/Center

America/North_Dakota/New_Salem

America/Rainy_River

America/Rankin_Inlet

America/Regina

America/Swift_Current

America/Tegucigalpa

America/Winnipeg

CST

CST6CDT

Canada/Central

Canada/East-Saskatchewan

Canada/Saskatchewan

Chile/EasterIsland

Etc/GMT+6

Mexico/General

Pacific/Easter

Pacific/Galapagos

SystemV/CST6

SystemV/CST6CDT

US/Central

US/Indiana-Starke

America/Atikokan

America/Bogota

America/Cayman

America/Coral_Harbour

America/Detroit

America/Eirunepe

America/Fort_Wayne

America/Grand_Turk

America/Guayaquil

America/Havana

America/Indiana/Indianapolis

America/Indiana/Marengo

America/Indiana/Petersburg

America/Indiana/Vevay

America/Indiana/Vincennes

America/Indiana/Winamac

America/Indianapolis

America/Iqaluit

America/Jamaica

America/Kentucky/Louisville

America/Kentucky/Monticello

America/Lima

America/Louisville

America/Montreal

America/Nassau

America/New_York

America/Nipigon

America/Panama

America/Pangnirtung

America/Port-au-Prince

America/Porto_Acre

America/Resolute

America/Rio_Branco

America/Thunder_Bay

America/Toronto

Brazil/Acre

Canada/Eastern

Cuba

EST

EST5EDT

Etc/GMT+5

IET

Jamaica

SystemV/EST5

SystemV/EST5EDT

US/East-Indiana

US/Eastern

US/Michigan

America/Caracas

America/Anguilla

America/Antigua

America/Aruba

America/Asuncion

America/Barbados

America/Blanc-Sablon

America/Boa_Vista

America/Campo_Grande

America/Cuiaba

America/Curacao

America/Dominica

America/Glace_Bay

America/Goose_Bay

America/Grenada

America/Guadeloupe

America/Guyana

America/Halifax

America/La_Paz

America/Manaus

America/Marigot

America/Martinique

America/Moncton

America/Montserrat

America/Port_of_Spain

America/Porto_Velho

America/Puerto_Rico

America/Santiago

America/Santo_Domingo

America/St_Barthelemy

America/St_Kitts

America/St_Lucia

America/St_Thomas

America/St_Vincent

America/Thule

America/Tortola

America/Virgin

Antarctica/Palmer

Atlantic/Bermuda

Atlantic/Stanley

Brazil/West

Canada/Atlantic

Chile/Continental

Etc/GMT+4

PRT

SystemV/AST4

SystemV/AST4ADT

America/St_Johns

CNT

Canada/Newfoundland

AGT

America/Araguaina

America/Argentina/Buenos_Aires

America/Argentina/Catamarca

America/Argentina/ComodRivadavia

America/Argentina/Cordoba

America/Argentina/Jujuy

America/Argentina/La_Rioja

America/Argentina/Mendoza

America/Argentina/Rio_Gallegos

America/Argentina/San_Juan

America/Argentina/San_Luis

America/Argentina/Tucuman

America/Argentina/Ushuaia

America/Bahia

America/Belem

America/Buenos_Aires

America/Catamarca

America/Cayenne

America/Cordoba

America/Fortaleza

America/Godthab

America/Jujuy

America/Maceio

America/Mendoza

America/Miquelon

America/Montevideo

America/Paramaribo

America/Recife

America/Rosario

America/Sao_Paulo

Antarctica/Rothera

BET

Brazil/East

Etc/GMT+3

America/Noronha

Atlantic/South_Georgia

Brazil/DeNoronha

Etc/GMT+2

America/Scoresbysund

Atlantic/Azores

Atlantic/Cape_Verde

Etc/GMT+1

Africa/Abidjan

Africa/Accra

Africa/Bamako

Africa/Banjul

Africa/Bissau

Africa/Casablanca

Africa/Conakry

Africa/Dakar

Africa/El_Aaiun

Africa/Freetown

Africa/Lome

Africa/Monrovia

Africa/Nouakchott

Africa/Ouagadougou

Africa/Sao_Tome

Africa/Timbuktu

America/Danmarkshavn

Atlantic/Canary

Atlantic/Faeroe

Atlantic/Faroe

Atlantic/Madeira

Atlantic/Reykjavik

Atlantic/St_Helena

Eire

Etc/GMT

Etc/GMT+0

Etc/GMT-0

Etc/GMT0

Etc/Greenwich

Etc/UCT

Etc/UTC

Etc/Universal

Etc/Zulu

Europe/Belfast

Europe/Dublin

Europe/Guernsey

Europe/Isle_of_Man

Europe/Jersey

Europe/Lisbon

Europe/London

GB

GB-Eire

GMT

GMT0

Greenwich

Iceland

Portugal

UCT

UTC

Universal

WET

Zulu

Africa/Algiers

Africa/Bangui

Africa/Brazzaville

Africa/Ceuta

Africa/Douala

Africa/Kinshasa

Africa/Lagos

Africa/Libreville

Africa/Luanda

Africa/Malabo

Africa/Ndjamena

Africa/Niamey

Africa/Porto-Novo

Africa/Tunis

Africa/Windhoek

Arctic/Longyearbyen

Atlantic/Jan_Mayen

CET

ECT

Etc/GMT-1

Europe/Amsterdam

Europe/Andorra

Europe/Belgrade

Europe/Berlin

Europe/Bratislava

Europe/Brussels

Europe/Budapest

Europe/Copenhagen

Europe/Gibraltar

Europe/Ljubljana

Europe/Luxembourg

Europe/Madrid

Europe/Malta

Europe/Monaco

Europe/Oslo

Europe/Paris

Europe/Podgorica

Europe/Prague

Europe/Rome

Europe/San_Marino

Europe/Sarajevo

Europe/Skopje

Europe/Stockholm

Europe/Tirane

Europe/Vaduz

Europe/Vatican

Europe/Vienna

Europe/Warsaw

Europe/Zagreb

Europe/Zurich

MET

Poland

ART

Africa/Blantyre

Africa/Bujumbura

Africa/Cairo

Africa/Gaborone

Africa/Harare

Africa/Johannesburg

Africa/Kigali

Africa/Lubumbashi

Africa/Lusaka

Africa/Maputo

Africa/Maseru

Africa/Mbabane

Africa/Tripoli

Asia/Amman

Asia/Beirut

Asia/Damascus

Asia/Gaza

Asia/Istanbul

Asia/Jerusalem

Asia/Nicosia

Asia/Tel_Aviv

CAT

EET

Egypt

Etc/GMT-2

Europe/Athens

Europe/Bucharest

Europe/Chisinau

Europe/Helsinki

Europe/Istanbul

Europe/Kaliningrad

Europe/Kiev

Europe/Mariehamn

Europe/Minsk

Europe/Nicosia

Europe/Riga

Europe/Simferopol

Europe/Sofia

Europe/Tallinn

Europe/Tiraspol

Europe/Uzhgorod

Europe/Vilnius

Europe/Zaporozhye

Israel

Libya

Turkey

Africa/Addis_Ababa

Africa/Asmara

Africa/Asmera

Africa/Dar_es_Salaam

Africa/Djibouti

Africa/Kampala

Africa/Khartoum

Africa/Mogadishu

Africa/Nairobi

Antarctica/Syowa

Asia/Aden

Asia/Baghdad

Asia/Bahrain

Asia/Kuwait

Asia/Qatar

Asia/Riyadh

EAT

Etc/GMT-3

Europe/Moscow

Europe/Volgograd

Indian/Antananarivo

Indian/Comoro

Indian/Mayotte

W-SU

Asia/Riyadh87

Asia/Riyadh88

Asia/Riyadh89

Mideast/Riyadh87

Mideast/Riyadh88

Mideast/Riyadh89

Asia/Tehran

Iran

Asia/Baku

Asia/Dubai

Asia/Muscat

Asia/Tbilisi

Asia/Yerevan

Etc/GMT-4

Europe/Samara

Indian/Mahe

Indian/Mauritius

Indian/Reunion

NET

Asia/Kabul

Asia/Aqtau

Asia/Aqtobe

Asia/Ashgabat

Asia/Ashkhabad

Asia/Dushanbe

Asia/Karachi

Asia/Oral

Asia/Samarkand

Asia/Tashkent

Asia/Yekaterinburg

Etc/GMT-5

Indian/Kerguelen

Indian/Maldives

PLT

Asia/Calcutta

Asia/Colombo

Asia/Kolkata

IST

Asia/Katmandu

Antarctica/Mawson

Antarctica/Vostok

Asia/Almaty

Asia/Bishkek

Asia/Dacca

Asia/Dhaka

Asia/Novosibirsk

Asia/Omsk

Asia/Qyzylorda

Asia/Thimbu

Asia/Thimphu

BST

Etc/GMT-6

Indian/Chagos

Asia/Rangoon

Indian/Cocos

Antarctica/Davis

Asia/Bangkok

Asia/Ho_Chi_Minh

Asia/Hovd

Asia/Jakarta

Asia/Krasnoyarsk

Asia/Phnom_Penh

Asia/Pontianak

Asia/Saigon

Asia/Vientiane

Etc/GMT-7

Indian/Christmas

VST

Antarctica/Casey

Asia/Brunei

Asia/Choibalsan

Asia/Chongqing

Asia/Chungking

Asia/Harbin

Asia/Hong_Kong

Asia/Irkutsk

Asia/Kashgar

Asia/Kuala_Lumpur

Asia/Kuching

Asia/Macao

Asia/Macau

Asia/Makassar

Asia/Manila

Asia/Shanghai

Asia/Singapore

Asia/Taipei

Asia/Ujung_Pandang

Asia/Ulaanbaatar

Asia/Ulan_Bator

Asia/Urumqi

Australia/Perth

Australia/West

CTT

Etc/GMT-8

Hongkong

PRC

Singapore

Australia/Eucla

Asia/Dili

Asia/Jayapura

Asia/Pyongyang

Asia/Seoul

Asia/Tokyo

Asia/Yakutsk

Etc/GMT-9

JST

Japan

Pacific/Palau

ROK

ACT

Australia/Adelaide

Australia/Broken_Hill

Australia/Darwin

Australia/North

Australia/South

Australia/Yancowinna

AET

Antarctica/DumontDUrville

Asia/Sakhalin

Asia/Vladivostok

Australia/ACT

Australia/Brisbane

Australia/Canberra

Australia/Currie

Australia/Hobart

Australia/Lindeman

Australia/Melbourne

Australia/NSW

Australia/Queensland

Australia/Sydney

Australia/Tasmania

Australia/Victoria

Etc/GMT-10

Pacific/Guam

Pacific/Port_Moresby

Pacific/Saipan

Pacific/Truk

Pacific/Yap

Australia/LHI

Australia/Lord_Howe

Asia/Magadan

Etc/GMT-11

Pacific/Efate

Pacific/Guadalcanal

Pacific/Kosrae

Pacific/Noumea

Pacific/Ponape

SST

Pacific/Norfolk

Antarctica/McMurdo

Antarctica/South_Pole

Asia/Anadyr

Asia/Kamchatka

Etc/GMT-12

Kwajalein

NST

NZ

Pacific/Auckland

Pacific/Fiji

Pacific/Funafuti

Pacific/Kwajalein

Pacific/Majuro

Pacific/Nauru

Pacific/Tarawa

Pacific/Wake

Pacific/Wallis

NZ-CHAT

Pacific/Chatham

Etc/GMT-13

Pacific/Enderbury

Pacific/Tongatapu

Etc/GMT-14

Pacific/Kiritimati

附： PostgreSQL Time Zone Names

NamesOffsetDescription

FJST

-13:00

Fiji Summer Time

FJT

-12:00

Fiji Time

IDLW

-12:00

International Date Line, West

BST

-11:00

Bering Summer Time

NT

-11:00

Nome Time

NUT

-11:00

Niue Time

AHST

-10:00

Alaska-Hawaii Std Time

CAT

-10:00

Central Alaska Time

HST

-10:00

Hawaii Std Time

THAT

-10:00

Tahiti Time

TKT

-10:00

Tokelau Time

MART

-09:30

Marquesas Time

AKST

-09:00

Alaska Standard Time

GAMT

-09:00

Gambier Time

HDT

-09:00

Hawaii/Alaska Daylight Time

YST

-09:00

Yukon Standard Time

AKDT

-08:00

Alaska Daylight Time

PST

-08:00

Pacific Standard Time

YDT

-08:00

Yukon Daylight Time

MST

-07:00

Mountain Standard Time

PDT

-07:00

Pacific Daylight Time

CST

-06:00

Central Standard Time

EAST

-06:00

Easter Island Time

GALT

-06:00

Galapagos Time

MDT

-06:00

Mountain Daylight Time

ZP6

-06:00

UTC +6 hours

ACT

-05:00

Atlantic/Porto Acre Time

CDT

-05:00

Central Daylight Time

COT

-05:00

Columbia Time

EASST

-05:00

Easter Island Summer Time

ECT

-05:00

Ecuador Time

EST

-05:00

Eastern Standard Time

PET

-05:00

Peru Time

ZP5

-05:00

UTC +5 hours

ACST

-04:00

Atlantic/Porto Acre Summer Time

AMT

-04:00

Amazon Time (Porto Velho)

AST

-04:00

Atlantic Std Time (Canada)

BOT

-04:00

Bolivia Time

CLT

-04:00

Chile Time

ECT

-04:00

Eastern Caribbean Time

EDT

-04:00

Eastern Daylight Time

GYT

-04:00

Guyana Time

PYT

-04:00

Paraguay Time

VET

-04:00

Venezuela Time

ZP4

-04:00

UTC +4 hours

NFT

-03:30

Newfoundland Standard Time

NST

-03:30

Newfoundland Standard Time

ADT

-03:00

Atlantic Daylight Time

AMST

-03:00

Amazon Summer Time (Porto Velho)

ART

-03:00

Argentina Time

AWT

-03:00

Brazil Time

BRT

-03:00

Brasilia Time

BST

-03:00

Brazil Standard Time

CLST

-03:00

Chile Summer Time

FKST

-03:00

Falkland Islands Summer Time

GFT

-03:00

French Guiana Time

PYST

-03:00

Paraguay Summer Time

UYT

-03:00

Uruguay Time

WGT

-03:00

West Greenland Time

NDT

-02:30

Newfoundland Daylight Time

BRST

-02:00

Brasilia Summer Time

FKT

-02:00

Falkland Islands Time

FNT

-02:00

Fernando de Noronha Time

PMDT

-02:00

Pierre & Miquelon Daylight Time

UYST

-02:00

Uruguay Summer Time

WGST

-02:00

West Greenland Summer Time

AZOT

-01:00

Azores Time

EGT

-01:00

East Greenland Time

FNST

-01:00

Fernando de Noronha Summer Time

SET

-01:00

Seychelles Time

WAT

-01:00

West Africa Time

AZOST

+00:00

Azores Summer Time

EGST

+00:00

East Greenland Summer Time

GMT

+00:00

Greenwich Mean Time

UTC

+00:00

Universal Coordinated Time

UT

+00:00

Universal Time

WET

+00:00

Western Europe

ZULU

+00:00

Universal Time

Z

+00:00

ISO-8601 Universal Time

BST

+01:00

British Summer Time

CET

+01:00

Central European Time

DNT

+01:00

Dansk Normal Time

FST

+01:00

French Summer Time

MET

+01:00

Middle Europe Time

MEWT

+01:00

Middle Europe Winter Time

MEZ

+01:00

Middle Europe Zone

NOR

+01:00

Norway Standard Time

SWT

+01:00

Swedish Winter Time

WEST

+01:00

Western Europe Summer Time

WEtdST

+01:00

Western Europe Daylight Savings Time

BDST

+02:00

British Double Summer Time

CEST

+02:00

Central European Dayl.Time

CETDST

+02:00

Central European Dayl.Time

EET

+02:00

Eastern Europe, USSR Zone 1

FWT

+02:00

French Winter Time

IST

+02:00

Israel Time

MEST

+02:00

Middle Europe Summer Time

MEtdST

+02:00

Middle Europe Daylight Time

SST

+02:00

Swedish Summer Time

BT

+03:00

Baghdad Time

EAT

+03:00

East Africa Time

EAT

+03:00

Indian Antananarivo Time

EEST

+03:00

Eastern Europe Summer Time

EEtdST

+03:00

Eastern Europe Daylight Time

HMT

+03:00

Hellas Mediterranean Time

MSK

+03:00

Moscow Time

IRT

+03:30

Iran Time

IT

+03:30

Iran Time

AMT

+04:00

Armenia Time (Yerevan)

AZT

+04:00

Azerbaijan Time

EAST

+04:00

Indian Antananarivo Savings Time

GET

+04:00

Georgia Time

MSD

+04:00

Moscow Summer Time

MUT

+04:00

Mauritius Island Time

RET

+04:00

Reunion Island Time

SCT

+04:00

Mahe Island Time

AFT

+04:30

Kabul Time

AMST

+05:00

Armenia Summer Time (Yerevan)

AZST

+05:00

Azerbaijan Summer Time

GEST

+05:00

Georgia Summer Time

IOT

+05:00

Indian Chagos Time

KGT

+05:00

Kyrgyzstan Time

MVT

+05:00

Maldives Island Time

PKT

+05:00

Pakistan Time

TFT

+05:00

Kerguelen Time

TJT

+05:00

Tajikistan Time

TMT

+05:00

Turkmenistan Time

UZT

+05:00

Uzbekistan Time

YEKT

+05:00

Yekaterinburg Time

NPT

+05:45

Nepal Standard Time

ALMT

+06:00

Almaty Time

BDT

+06:00

Dacca Time

BTT

+06:00

Bhutan Time

DUSST

+06:00

Dushanbe Summer Time

KGST

+06:00

Kyrgyzstan Summer Time

LKT

+06:00

Lanka Time

MAWT

+06:00

Mawson, Antarctica

NOVT

+06:00

Novosibirsk Standard Time

OMST

+06:00

Omsk Time

UZST

+06:00

Uzbekistan Summer Time

YEKST

+06:00

Yekaterinburg Summer Time

CCT

+06:30

Indian Cocos (Island) Time

MMT

+06:30

Myanmar Time

ALMST

+07:00

Almaty Savings Time

CVT

+07:00

Christmas Island Time (Indian Ocean)

CXT

+07:00

Christmas Island Time (Indian Ocean)

DAVT

+07:00

Davis Time (Antarctica)

ICT

+07:00

Indochina Time

JAVT

+07:00

Java Time

KRAST

+07:00

Krasnoyarsk Summer Time

NOVST

+07:00

Novosibirsk Summer Time

OMSST

+07:00

Omsk Summer Time

WAST

+07:00

West Australian Std Time

JT

+07:30

Java Time

AWST

+08:00

Western Australia

BNT

+08:00

Brunei Darussalam Time

BORT

+08:00

Borneo Time (Indonesia)

CCT

+08:00

China Coast Time

HKT

+08:00

Hong Kong Time

IRKT

+08:00

Irkutsk Time

KRAT

+08:00

Krasnoyarsk Standard Time

MYT

+08:00

Malaysia Time

PHT

+08:00

Phillipine Time

ULAT

+08:00

Ulan Bator Time

WADT

+08:00

West Australian DST

WST

+08:00

West Australian Standard   Time

MT

+08:30

Moluccas Time

AWSST

+09:00

Western Australia Time

IRKST

+09:00

Irkutsk Summer Time

JAYT

+09:00

Jayapura Time (Indonesia)

JST

+09:00

Japan Std Time, USSR Zone 8

KST

+09:00

Korea Standard Time

PWT

+09:00

Palau Time

ULAST

+09:00

Ulan Bator Summer Time

WDT

+09:00

West Australian DST

YAKT

+09:00

Yakutsk Time

ACST

+09:30

Central Australia

CAST

+09:30

Central Australian ST

SAST

+09:30

South Australian Std Time

SAT

+09:30

South Australian Std Time

AEST

+10:00

Australia Eastern Std Time

DDUT

+10:00

Dumont-d'Urville Time (Antarctica)

EAST

+10:00

East Australian Std Time

EST

+10:00

Australia Eastern Std Time

GST

+10:00

Guam Std Time, USSR Zone 9

KDT

+10:00

Korea Daylight Time

LIGT

+10:00

From Melbourne, Australia

MPT

+10:00

North Mariana Islands Time

PGT

+10:00

Papua New Guinea Time

trUK

+10:00

Truk Time

VLAT

+10:00

Vladivostok Time

YAKST

+10:00

Yakutsk Summer Time

YAPT

+10:00

Yap Time (Micronesia)

ACSST

+10:30

Central Australia Time

CADT

+10:30

Central Australian DST

CST

+10:30

Australia Central Std Time

LHST

+10:30

Lord Howe Standard Time, Australia

SADT

+10:30

South Australian Daylight Time

AESST

+11:00

Eastern Australia

LHDT

+11:00

Lord Howe Daylight Time, Australia

MAGT

+11:00

Magadan Time

NCT

+11:00

New Caledonia Time

PONT

+11:00

Ponape Time (Micronesia)

VLAST

+11:00

Vladivostok Summer Time

VUT

+11:00

Vanuata Time

ANAT

+12:00

Anadyr Time (Russia)

CKT

+12:00

Cook Islands Time

GILT

+12:00

Gilbert Islands Time

IDLE

+12:00

International Date Line, East

KOST

+12:00

Kosrae Time

MAGST

+12:00

Magadan Summer Time

MHT

+12:00

Kwajalein Time

NZST

+12:00

New Zealand Standard Time

NZT

+12:00

New Zealand Time

PETT

+12:00

Petropavlovsk-Kamchatski Time

TVT

+12:00

Tuvalu Time

WAKT

+12:00

Wake Time

WFT

+12:00

Wallis and Futuna Time

CHAST

+12:45

Chatham Island Time

ANAST

+13:00

Anadyr Summer Time (Russia)

NZDT

+13:00

New Zealand Daylight Time

PETST

+13:00

Petropavlovsk-Kamchatski Summer Time

PHOT

+13:00

Phoenix Islands (Kiribati) Time

TOT

+13:00

Tonga Time

CHADT

+13:45

Chatham Island Daylight Time

LINT

+14:00

Line Islands Time (Kiribati)