Cambiar zona horaria en PHP (date_default_timezone_set)

Algo importante que se debe hacer en un sitio web es permitir que los usuarios establezcan la zona horaria donde viven, de modo que la hora de todas las operaciones hechas dicho o usuario o por el sistema para servir a ese usuario usen la hora adecuada.

Recordemos que un sitio web puede ser visto en cualquier parte del mundo y la hora del servidor web no es la hora que tienen todos los usuarios en el mundo.

PHP permite establecer la zona horaria, a través de la función: date_default_timezone_set(“zona horaria”)

ejemplo: date_default_timezone_set("Africa/Addis_Ababa");


Los valores admisibles se pueden encontrar en cualquier manual de PHP:

Grupos de Africa:

Africa/Abidjan	Africa/Accra	Africa/Addis_Ababa	Africa/Algiers	Africa/Asmera
Africa/Bamako	Africa/Bangui	Africa/Banjul	Africa/Bissau	Africa/Blantyre
Africa/Brazzaville	Africa/Bujumbura	Africa/Cairo	Africa/Casablanca	Africa/Ceuta
Africa/Conakry	Africa/Dakar	Africa/Dar_es_Salaam	Africa/Djibouti	Africa/Douala
Africa/El_Aaiun	Africa/Freetown	Africa/Gaborone	Africa/Harare	Africa/Johannesburg
Africa/Kampala	Africa/Khartoum	Africa/Kigali	Africa/Kinshasa	Africa/Lagos
Africa/Libreville	Africa/Lome	Africa/Luanda	Africa/Lubumbashi	Africa/Lusaka
Africa/Malabo	Africa/Maputo	Africa/Maseru	Africa/Mbabane	Africa/Mogadishu
Africa/Monrovia	Africa/Nairobi	Africa/Ndjamena	Africa/Niamey	Africa/Nouakchott
Africa/Ouagadougou	Africa/Porto-Novo	Africa/Sao_Tome	Africa/Timbuktu	Africa/Tripoli

Grupos de América

America/Adak	America/Anchorage	America/Anguilla	America/Antigua	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/Tucuman
America/Argentina/Ushuaia	America/Aruba	America/Asuncion	America/Atikokan	America/Atka
America/Bahia	America/Barbados	America/Belem	America/Belize	America/Blanc-Sablon
America/Boa_Vista	America/Bogota	America/Boise	America/Buenos_Aires	America/Cambridge_Bay
America/Campo_Grande	America/Cancun	America/Caracas	America/Catamarca	America/Cayenne
America/Cayman	America/Chicago	America/Chihuahua	America/Coral_Harbour	America/Cordoba
America/Costa_Rica	America/Cuiaba	America/Curacao	America/Danmarkshavn	America/Dawson
America/Dawson_Creek	America/Denver	America/Detroit	America/Dominica	America/Edmonton
America/Eirunepe	America/El_Salvador	America/Ensenada	America/Fort_Wayne	America/Fortaleza
America/Glace_Bay	America/Godthab	America/Goose_Bay	America/Grand_Turk	America/Grenada
America/Guadeloupe	America/Guatemala	America/Guayaquil	America/Guyana	America/Halifax
America/Havana	America/Hermosillo	America/Indiana/Indianapolis	America/Indiana/Knox	America/Indiana/Marengo
America/Indiana/Petersburg	America/Indiana/Vevay	America/Indiana/Vincennes	America/Indianapolis	America/Inuvik
America/Iqaluit	America/Jamaica	America/Jujuy	America/Juneau	America/Kentucky/Louisville
America/Kentucky/Monticello	America/Knox_IN	America/La_Paz	America/Lima	America/Los_Angeles
America/Louisville	America/Maceio	America/Managua	America/Manaus	America/Martinique
America/Mazatlan	America/Mendoza	America/Menominee	America/Merida	America/Mexico_City
America/Miquelon	America/Moncton	America/Monterrey	America/Montevideo	America/Montreal
America/Montserrat	America/Nassau	America/New_York	America/Nipigon	America/Nome
America/Noronha	America/North_Dakota/Center	America/North_Dakota/New_Salem	America/Panama	America/Pangnirtung
America/Paramaribo	America/Phoenix	America/Port-au-Prince	America/Port_of_Spain	America/Porto_Acre
America/Porto_Velho	America/Puerto_Rico	America/Rainy_River	America/Rankin_Inlet	America/Recife
America/Regina	America/Rio_Branco	America/Rosario	America/Santiago	America/Santo_Domingo
America/Sao_Paulo	America/Scoresbysund	America/Shiprock	America/St_Johns	America/St_Kitts
America/St_Lucia	America/St_Thomas	America/St_Vincent	America/Swift_Current	America/Tegucigalpa
America/Thule	America/Thunder_Bay	America/Tijuana	America/Toronto	America/Tortola
America/Vancouver	America/Virgin	America/Whitehorse	America/Winnipeg	America/Yakutat

Grupos de La Antártida

Antarctica/Casey	Antarctica/Davis	Antarctica/DumontDUrville	Antarctica/Mawson	Antarctica/McMurdo
Antarctica/Palmer	Antarctica/Rothera	Antarctica/South_Pole	Antarctica/Syowa	Antarctica/Vostok

Grupos del Ártico

Arctic/Longyearbyen

Grupos de Asia

Asia/Aden	Asia/Almaty	Asia/Amman	Asia/Anadyr	Asia/Aqtau
Asia/Aqtobe	Asia/Ashgabat	Asia/Ashkhabad	Asia/Baghdad	Asia/Bahrain
Asia/Baku	Asia/Bangkok	Asia/Beirut	Asia/Bishkek	Asia/Brunei
Asia/Calcutta	Asia/Choibalsan	Asia/Chongqing	Asia/Chungking	Asia/Colombo
Asia/Dacca	Asia/Damascus	Asia/Dhaka	Asia/Dili	Asia/Dubai
Asia/Dushanbe	Asia/Gaza	Asia/Harbin	Asia/Hong_Kong	Asia/Hovd
Asia/Irkutsk	Asia/Istanbul	Asia/Jakarta	Asia/Jayapura	Asia/Jerusalem
Asia/Kabul	Asia/Kamchatka	Asia/Karachi	Asia/Kashgar	Asia/Katmandu
Asia/Krasnoyarsk	Asia/Kuala_Lumpur	Asia/Kuching	Asia/Kuwait	Asia/Macao
Asia/Macau	Asia/Magadan	Asia/Makassar	Asia/Manila	Asia/Muscat
Asia/Nicosia	Asia/Novosibirsk	Asia/Omsk	Asia/Oral	Asia/Phnom_Penh
Asia/Pontianak	Asia/Pyongyang	Asia/Qatar	Asia/Qyzylorda	Asia/Rangoon
Asia/Riyadh	Asia/Saigon	Asia/Sakhalin	Asia/Samarkand	Asia/Seoul
Asia/Shanghai	Asia/Singapore	Asia/Taipei	Asia/Tashkent	Asia/Tbilisi
Asia/Tehran	Asia/Tel_Aviv	Asia/Thimbu	Asia/Thimphu	Asia/Tokyo
Asia/Ujung_Pandang	Asia/Ulaanbaatar	Asia/Ulan_Bator	Asia/Urumqi	Asia/Vientiane
Asia/Vladivostok	Asia/Yakutsk	Asia/Yekaterinburg	Asia/Yerevan

Grupos del Atlántico

Atlantic/Azores	Atlantic/Bermuda	Atlantic/Canary	Atlantic/Cape_Verde	Atlantic/Faeroe
Atlantic/Jan_Mayen	Atlantic/Madeira	Atlantic/Reykjavik	Atlantic/South_Georgia	Atlantic/St_Helena
Atlantic/Stanley

Grupos de Australia

Australia/ACT	Australia/Adelaide	Australia/Brisbane	Australia/Broken_Hill	Australia/Canberra
Australia/Currie	Australia/Darwin	Australia/Hobart	Australia/LHI	Australia/Lindeman
Australia/Lord_Howe	Australia/Melbourne	Australia/North	Australia/NSW	Australia/Perth
Australia/Queensland	Australia/South	Australia/Sydney	Australia/Tasmania	Australia/Victoria
Australia/West	Australia/Yancowinna

Grupos de Europa

Europe/Amsterdam	Europe/Andorra	Europe/Athens	Europe/Belfast	Europe/Belgrade
Europe/Berlin	Europe/Bratislava	Europe/Brussels	Europe/Bucharest	Europe/Budapest
Europe/Chisinau	Europe/Copenhagen	Europe/Dublin	Europe/Gibraltar	Europe/Guernsey
Europe/Helsinki	Europe/Isle_of_Man	Europe/Istanbul	Europe/Jersey	Europe/Kaliningrad
Europe/Kiev	Europe/Lisbon	Europe/Ljubljana	Europe/London	Europe/Luxembourg
Europe/Madrid	Europe/Malta	Europe/Mariehamn	Europe/Minsk	Europe/Monaco
Europe/Moscow	Europe/Nicosia	Europe/Oslo	Europe/Paris	Europe/Prague
Europe/Riga	Europe/Rome	Europe/Samara	Europe/San_Marino	Europe/Sarajevo
Europe/Simferopol	Europe/Skopje	Europe/Sofia	Europe/Stockholm	Europe/Tallinn
Europe/Tirane	Europe/Tiraspol	Europe/Uzhgorod	Europe/Vaduz	Europe/Vatican
Europe/Vienna	Europe/Vilnius	Europe/Volgograd	Europe/Warsaw	Europe/Zagreb
Europe/Zaporozhye	Europe/Zurich

Grupos de India

Indian/Antananarivo	Indian/Chagos	Indian/Christmas	Indian/Cocos	Indian/Comoro
Indian/Kerguelen	Indian/Mahe	Indian/Maldives	Indian/Mauritius	Indian/Mayotte
Indian/Reunion

Grupos del Pacifico

Pacific/Apia	Pacific/Auckland	Pacific/Chatham	Pacific/Easter	Pacific/Efate
Pacific/Enderbury	Pacific/Fakaofo	Pacific/Fiji	Pacific/Funafuti	Pacific/Galapagos
Pacific/Gambier	Pacific/Guadalcanal	Pacific/Guam	Pacific/Honolulu	Pacific/Johnston
Pacific/Kiritimati	Pacific/Kosrae	Pacific/Kwajalein	Pacific/Majuro	Pacific/Marquesas
Pacific/Midway	Pacific/Nauru	Pacific/Niue	Pacific/Norfolk	Pacific/Noumea
Pacific/Pago_Pago	Pacific/Palau	Pacific/Pitcairn	Pacific/Ponape	Pacific/Port_Moresby
Pacific/Rarotonga	Pacific/Saipan	Pacific/Samoa	Pacific/Tahiti	Pacific/Tarawa
Pacific/Tongatapu	Pacific/Truk	Pacific/Wake	Pacific/Wallis	Pacific/Yap

Otros grupos

Brazil/Acre	Brazil/DeNoronha	Brazil/East	Brazil/West	Canada/Atlantic
Canada/Central	Canada/East-Saskatchewan	Canada/Eastern	Canada/Mountain	Canada/Newfoundland
Canada/Pacific	Canada/Saskatchewan	Canada/Yukon	CET	Chile/Continental
Chile/EasterIsland	CST6CDT	Cuba	EET	Egypt
Eire	EST	EST5EDT	Etc/GMT	Etc/GMT+0
Etc/GMT+1	Etc/GMT+10	Etc/GMT+11	Etc/GMT+12	Etc/GMT+2
Etc/GMT+3	Etc/GMT+4	Etc/GMT+5	Etc/GMT+6	Etc/GMT+7
Etc/GMT+8	Etc/GMT+9	Etc/GMT-0	Etc/GMT-1	Etc/GMT-10
Etc/GMT-11	Etc/GMT-12	Etc/GMT-13	Etc/GMT-14	Etc/GMT-2
Etc/GMT-3	Etc/GMT-4	Etc/GMT-5	Etc/GMT-6	Etc/GMT-7
Etc/GMT-8	Etc/GMT-9	Etc/GMT0	Etc/Greenwich	Etc/UCT
Etc/Universal	Etc/UTC	Etc/Zulu	Factory	GB
GB-Eire	GMT	GMT+0	GMT-0	GMT0
Greenwich	Hongkong	HST	Iceland	Iran
Israel	Jamaica	Japan	Kwajalein	Libya
MET	Mexico/BajaNorte	Mexico/BajaSur	Mexico/General	MST
MST7MDT	Navajo	NZ	NZ-CHAT	Poland
Portugal	PRC	PST8PDT	ROC	ROK
Singapore	Turkey	UCT	Universal	US/Alaska
US/Aleutian	US/Arizona	US/Central	US/East-Indiana	US/Eastern
US/Hawaii	US/Indiana-Starke	US/Michigan	US/Mountain	US/Pacific
US/Pacific-New	US/Samoa	UTC	W-SU	WET
Zulu

Códicos internacionales de cada zona horaria

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Código	Definición	GMT
ACDT	Australian Central Daylight Time	+10:30
ACIT	Ashmore and Cartier Islands Time	+8:00
ACST	Australian Central Standard Time	+9:30
ACT	Acre Time	-5
ACWST	Australian Central Western Standard Time	+8:45
ADT	Arabia Daylight Time	+4
ADT	Atlantic Daylight Time	-3
AEDT	Australian Eastern Daylight Time	+11
AEST	Australian Eastern Standard Time	+10
AFT	Afghanistan Time	+4:30
AKDT	Alaska Daylight Time	-8
AKST	Alaska Standard Time	-9
AMDT	Armenia Daylight Time	+5
AMST	Armenia Standard Time	+4
ANAST	Anadyr' Summer Time	+13
ANAT	Anadyr' Time	+12
APO	Apo Island Time	+8:15
ARDT	Argentina Daylight Time	-2
ART	Argentina Time	-3
AST	Al Manamah Standard Time	+3
AST	Arabia Standard Time	+3
AST	Arabic Standard Time	+3
AST	Atlantic Standard Time	-4
AWST	Australian Western Standard Time	+8
AZODT	Azores Daylight Time	0
AZOST	Azores Standard Time	-1
AZST	Azerbaijan Summer Time	+5
AZT	Azerbaijan Time	+4
BIT	Baker Island Time	-12
BDT	Bangladesh Standard Time	+7
BEST	Brazil Eastern Standard Time	-2
BDT	Brunei Time	+8
BIOT	British Indian Ocean Time	+6
BOT	Bolivia Time	-4
BRST	Brazilia Summer Time	-2
BRT	Brazilia Time	-3
BST	British Summer Time	+1
BTT	Bhutan Time	+6
BWDT	Brazil Western Daylight Time	-3
BWST	Brazil Western Standard Time	-4
CAST	Chinese Antarctic Standard Time	+5
CAT	Central Africa Time	+2
CCT	Cocos Islands Time	+6:30
CDT	Central Daylight Time	-5
CEST	Central Europe Summer Time	+2
CET	Central Europe Time	+1
CGST	Central Greenland Summer Time	-2
CGT	Central Greenland Time	-3
CHADT	Chatham Island Daylight Time	+13:45
CHAST	Chatham Island Standard Time	+12:45
ChST	Chamorro Standard Time	+10
CIST	Clipperton Island Standard Time	-8
CKT	Cook Island Time	-10
CLDT	Chile Daylight Time	-3
CLST	Chile Standard Time	-4
COT	Colombia Time	-5
CST	Central Standard Time	-6
CST	China Standard Time	+8
CVT	Cape Verde Time	-1
CXT	Christmas Island Time	+7
DAVT	Davis Time	+5
DTAT	District de Terre Adélie Time	+10
EADT	Easter Island Daylight Time	-5
EAST	Easter Island Standard Time	-6
EAT	East Africa Time	+3
ECT	Ecuador Time	-5
EDT	Eastern Daylight Time	-4
EEST	Eastern Europe Summer Time	+3
EET	Eastern Europe Time	+2
EGT	Eastern Greenland Time	-1
EGST	Eastern Greenland Summer Time	0
EKST	East Kazakhstan Standard Time	+6
EST	Eastern Standard Time	-5
FJDT	Fiji Daylight Time	+13
FJT	Fiji Time	+12
FKDT	Falkland Island Daylight Time	-3
FKST	Falkland Island Standard Time	-4
GALT	Galapagos Time	-6
GET	Georgia Standard Time	+4
GFT	French Guiana Time	-3
GILT	Gilbert Island Time	+12
GIT	Gambier Island Time	-9
GMT	Greenwich Meantime	0
GST	Gulf Standard Time	+4
GST	South Georgia and the South Sandwich Islands	-2
GYT	Guyana Time	-4
HADT	Hawaii - Aleutian Daylight Time	-9
HAST	Hawaii - Aleutian Standard Time	-10
HKST	Hong Kong Standard Time	+8
HMT	Heard and McDonald Islands Time	+5
ICT	Îles Crozet Time	+4
ICT	Indochina Time	+7
IDT	Ireland Daylight Time	+1
IDT	Israel Daylight Time	+3
IRDT	Îran Daylight Time	+4:30
IRKST	Irkutsk Summer Time	+9
IRKT	Irkutsk Time	+8
IRST	Îran Standard Time	+3:30
IST	Indian Standard Time	+5:30
IST	Ireland Standard Time	0
IST	Israel Standard Time	+2
JFDT	Juan Fernandez Islands Daylight Time	-3
JFST	Juan Fernandez Islands Standard Time	-4
JST	Japan Standard Time	+9
KGST	Kyrgyzstan Summer Time	+6
KGT	Kyrgyzstan Time	+5
KRAST	Krasnoyarsk Summer Time	+8
KRAT	Krasnoyarsk Time	+7
KOST	Kosrae Standard Time	+11
KOVT	Khovd Time	+7
KOVST	Khovd Summer Time	+8
KST	Korea Standard Time	+9
LHDT	Lord Howe Daylight Time	+11
LHST	Lord Howe Standard Time	+10:30
LINT	Line Island Time	+14
LKT	Sri Lanka Time	+6
MAGST	Magadan Island Summer Time	+12
MAGT	Magadan Island Time	+11
MAWT	Mawson Time	+5
MBT	Macclesfield Bank Time	+8
MDT	Mountain Daylight Time	-6
MIT	Marquesas Islands Time	-9:30
MHT	Marshall Islands Time	+12
MMT	Myanmar Time	+6:30
MNT	Mongolia Time	+8
MNST	Mongolia Summer Time	+9
MSD	Moscow Summer Time	+4
MSK	Moscow Standard Time	+3
MST	Mountain Standard Time	-7
MUT	Mauritius Time	+4
MVT	Maldives Time	+5
MYT	Malaysia Time	+8
NCT	New Caledonia Time	+11
NDT	Newfoundland Daylight Time	-2:30
NFT	Norfolk Time	+11:30
NPT	Nepal Time	+5:45
NRT	Nauru Time	+12
NOVST	Novosibirsk Summer Time	+7
NOVT	Novosibirsk Time	+6
NST	Newfoundland Standard Time	-3:30
NUT	Niue Time	-11
NZDT	New Zealand Daylight Time	+13
NZST	New Zealand Standard Time	+12
OMSK	Omsk Summer Time	+7
OMST	Omsk Standard Time	+6
PDT	Pacific Daylight Time	-7
PETST	Petropavlovsk Summer Time	+13
PET	Peru Time	-5
PETT	Petropavlovsk Time	+12
PGT	Papua New Guinea Time	+10
PHOT	Phoenix Island Time	+13
PIT	Paracel Islands Time	+8
PIT	Peter Island Time	-6
PIT	Pratas Islands	+8
PKT	Pakistan Time	+5
PKST	Pakistan Summer Time	+6
PMDT	Pierre & Miquelon Daylight Time	-2
PMST	Pierre & Miquelon Standard Time	-3
PONT	Pohnpei Standard Time	+11
PST	Pacific Standard Time	-8
PST	Philippine Standar Time	+8
PST	Pitcairn Standard Time	-8
PWT	Palau Time	+9
PYST	Paraguay Summer Time	-3
PYT	Paraguay Time	-4
RET	Réunion Time	+4
ROTT	Rothera Time	-3
SAMST	Samara Summer Time	+5
SAMT	Samara Time	+4
SAST	South Africa Standard Time	+2
SBT	Solomon Island Time	+11
SCDT	Santa Claus Delivery Time	+13
SCST	Santa Claus Standard Time	+12
SCT	Seychelles Time	+4
SGT	Singapore Time	+8
SIT	Spratly Islands Time	+8
SLT	San Luis Time	-4
SLT	Sierra Leone Time	0
SLST	San Luis Summer Time	-3
SRT	Suriname Time	-3
SDT	Samoa Daylight Time	-10
SST	Samoa Standard Time	-11
SST	Scarborough Shoal Time	+8
SYST	Syrian Summer Time	+3
SYT	Syrian Standard Time	+2
TAHT	Tahiti Time	-10
TFT	French Southern and Antarctic Time	+5
TJT	Tajikistan Time	+5
TKT	Tokelau Time	-10
TMT	Turkmenistan Time	+5
TOT	Tonga Time	+13
TPT	East Timor Time	+9
TRUT	Truk Time	+10
TVT	Tuvalu Time	+12
TWT	Taiwan Time	+8
UTC	Universal Coordinated Time	0
UYT	Uruguay Standard Time	-3
UYST	Uruguay Summer Time	-2
UZT	Uzbekistan Time	+5
VLAST	Vladivostok Summer Time	+11
VLAT	Vladivostok Time	+10
VOST	Vostok Time	+6
VST	Venezuela Standard Time	-4:30
VUT	Vanuatu Time	+11
WAST	Western Africa Summer Time	+2
WAT	Western Africa Time	+1
WEST	Western Europe Summer Time	+1
WET	Western Europe Time	0
WFT	Wallis and Futuna Time	+12
WIB	Waktu Indonesia Bagian Barat	+7
WIT	Waktu Indonesia Bagian Timur	+9
WITA	Waktu Indonesia Bagian Tengah	+8
WKST	West Kazakhstan Standard Time	+5
XJT	Xinjiang Standard Time	+6
YAKST	Yakutsk Summer Time	+10
YAKT	Yakutsk Time	+9
YAPT	Yap Time	+10
YEKST	Yekaterinburg Summer Time	+6
YEKT	Yekaterinburg Time	+5

Moises Soft (Desarrollo web en Cuba)