Timezone abbreviations
Timezone abbreviations are not a standard. They are local convention, they collide across regions, and no library resolves them reliably — which is why every entry below also gives the IANA zone name you should actually put in code. Offsets shown are what the abbreviation denotes; the live column is the current time in a representative zone that uses it.
All abbreviations 73 entries · sorted by UTC offset
| Abbr | Name | Offset | Time now | IANA zone for code | Page |
|---|---|---|---|---|---|
| SST | Samoa Standard Time Oceania |
-11:00 | 12:25 SST | Pacific/Pago_Pago | SST → |
| HST | Hawaii Standard Time Oceania |
-10:00 | 13:25 HST | Pacific/Honolulu | HST → |
| AKST | Alaska Standard Time North America |
-09:00 | 15:25 AKDT | America/Anchorage | AKST → |
| AKDT | Alaska Daylight Time North America |
-08:00 | 15:25 AKDT | America/Anchorage | AKDT → |
| PST ambiguous | Pacific Standard Time North America |
-08:00 | 16:25 PDT | America/Los_Angeles | PST → |
| PST ambiguous | Philippine Standard Time Asia |
+08:00 | 07:25 PST | Asia/Manila | PST → |
| MST ambiguous | Mountain Standard Time North America |
-07:00 | 17:25 MDT | America/Denver | MST → |
| MST ambiguous | Myanmar Standard Time Asia |
+06:30 | 05:55 UTC+06:30 | Asia/Yangon | MST → |
| PDT | Pacific Daylight Time North America |
-07:00 | 16:25 PDT | America/Los_Angeles | PDT → |
| CST ambiguous | Central Standard Time North America |
-06:00 | 18:25 CDT | America/Chicago | CST → |
| CST ambiguous | China Standard Time Asia |
+08:00 | 07:25 CST | Asia/Shanghai | CST → |
| CST ambiguous | Cuba Standard Time Caribbean |
-05:00 | 19:25 CDT | America/Havana | CST → |
| MDT | Mountain Daylight Time North America |
-06:00 | 17:25 MDT | America/Denver | MDT → |
| CDT ambiguous | Central Daylight Time North America |
-05:00 | 18:25 CDT | America/Chicago | CDT → |
| CDT ambiguous | Cuba Daylight Time Caribbean |
-04:00 | 19:25 CDT | America/Havana | CDT → |
| COT | Colombia Time South America |
-05:00 | 18:25 UTC-05:00 | America/Bogota | COT → |
| EST ambiguous | Eastern Standard Time North America |
-05:00 | 19:25 EDT | America/New_York | EST → |
| EST ambiguous | Eastern Standard Time (Australia) Oceania |
+10:00 | 09:25 AEST | Australia/Sydney | EST → |
| PET | Peru Time South America |
-05:00 | 18:25 UTC-05:00 | America/Lima | PET → |
| AST ambiguous | Atlantic Standard Time North America |
-04:00 | 20:25 ADT | America/Halifax | AST → |
| AST ambiguous | Arabia Standard Time Asia |
+03:00 | 02:25 UTC+03:00 | Asia/Riyadh | AST → |
| CLT | Chile Standard Time South America |
-04:00 | 19:25 UTC-04:00 | America/Santiago | CLT → |
| EDT | Eastern Daylight Time North America |
-04:00 | 19:25 EDT | America/New_York | EDT → |
| VET | Venezuela Time South America |
-04:00 | 19:25 UTC-04:00 | America/Caracas | VET → |
| NST | Newfoundland Standard Time North America |
-03:30 | 20:55 NDT | America/St_Johns | NST → |
| ADT | Atlantic Daylight Time North America |
-03:00 | 20:25 ADT | America/Halifax | ADT → |
| ART | Argentina Time South America |
-03:00 | 20:25 UTC-03:00 | America/Argentina/Buenos_Aires | ART → |
| BRT | Brasília Time South America |
-03:00 | 20:25 UTC-03:00 | America/Sao_Paulo | BRT → |
| AZOT | Azores Time Atlantic |
-01:00 | 23:25 UTC+00:00 | Atlantic/Azores | AZOT → |
| GMT | Greenwich Mean Time Europe / Africa |
+00:00 | 23:25 GMT | Etc/GMT | GMT → |
| UTC | Coordinated Universal Time Worldwide |
+00:00 | 23:25 UTC | UTC | UTC → |
| WET | Western European Time Europe |
+00:00 | 00:25 WEST | Europe/Lisbon | WET → |
| BST ambiguous | British Summer Time Europe |
+01:00 | 00:25 BST | Europe/London | BST → |
| BST ambiguous | Bangladesh Standard Time Asia |
+06:00 | 05:25 UTC+06:00 | Asia/Dhaka | BST → |
| CET | Central European Time Europe |
+01:00 | 01:25 CEST | Europe/Paris | CET → |
| WAT | West Africa Time Africa |
+01:00 | 00:25 WAT | Africa/Lagos | WAT → |
| WEST | Western European Summer Time Europe |
+01:00 | 00:25 WEST | Europe/Lisbon | WEST → |
| CAT | Central Africa Time Africa |
+02:00 | 01:25 CAT | Africa/Harare | CAT → |
| CEST | Central European Summer Time Europe |
+02:00 | 01:25 CEST | Europe/Paris | CEST → |
| EET | Eastern European Time Europe |
+02:00 | 02:25 EEST | Europe/Athens | EET → |
| SAST | South Africa Standard Time Africa |
+02:00 | 01:25 SAST | Africa/Johannesburg | SAST → |
| EAT | East Africa Time Africa |
+03:00 | 02:25 EAT | Africa/Nairobi | EAT → |
| EEST | Eastern European Summer Time Europe |
+03:00 | 02:25 EEST | Europe/Athens | EEST → |
| IDT | Israel Daylight Time Asia |
+03:00 | 02:25 IDT | Asia/Jerusalem | IDT → |
| MSK | Moscow Standard Time Europe |
+03:00 | 02:25 MSK | Europe/Moscow | MSK → |
| IRST | Iran Standard Time Asia |
+03:30 | 02:55 UTC+03:30 | Asia/Tehran | IRST → |
| GST ambiguous | Gulf Standard Time Asia |
+04:00 | 03:25 UTC+04:00 | Asia/Dubai | GST → |
| GST ambiguous | South Georgia Time South Atlantic |
-02:00 | 21:25 UTC-02:00 | Atlantic/South_Georgia | GST → |
| AFT | Afghanistan Time Asia |
+04:30 | 03:55 UTC+04:30 | Asia/Kabul | AFT → |
| PKT | Pakistan Standard Time Asia |
+05:00 | 04:25 PKT | Asia/Karachi | PKT → |
| IST ambiguous | India Standard Time Asia |
+05:30 | 04:55 IST | Asia/Kolkata | IST → |
| IST ambiguous | Irish Standard Time Europe |
+01:00 | 00:25 IST | Europe/Dublin | IST → |
| IST ambiguous | Israel Standard Time Asia |
+02:00 | 02:25 IDT | Asia/Jerusalem | IST → |
| NPT | Nepal Time Asia |
+05:45 | 05:10 UTC+05:45 | Asia/Kathmandu | NPT → |
| ICT | Indochina Time Asia |
+07:00 | 06:25 UTC+07:00 | Asia/Bangkok | ICT → |
| WIB | Western Indonesian Time Asia |
+07:00 | 06:25 WIB | Asia/Jakarta | WIB → |
| AWST | Australian Western Standard Time Oceania |
+08:00 | 07:25 AWST | Australia/Perth | AWST → |
| HKT | Hong Kong Time Asia |
+08:00 | 07:25 HKT | Asia/Hong_Kong | HKT → |
| MYT | Malaysia Time Asia |
+08:00 | 07:25 UTC+08:00 | Asia/Kuala_Lumpur | MYT → |
| PHT | Philippine Time Asia |
+08:00 | 07:25 PST | Asia/Manila | PHT → |
| SGT | Singapore Time Asia |
+08:00 | 07:25 UTC+08:00 | Asia/Singapore | SGT → |
| WITA | Central Indonesian Time Asia |
+08:00 | 07:25 WITA | Asia/Makassar | WITA → |
| JST | Japan Standard Time Asia |
+09:00 | 08:25 JST | Asia/Tokyo | JST → |
| KST | Korea Standard Time Asia |
+09:00 | 08:25 KST | Asia/Seoul | KST → |
| WIT | Eastern Indonesian Time Asia |
+09:00 | 08:25 WIT | Asia/Jayapura | WIT → |
| ACST | Australian Central Standard Time Oceania |
+09:30 | 08:55 ACST | Australia/Adelaide | ACST → |
| AEST | Australian Eastern Standard Time Oceania |
+10:00 | 09:25 AEST | Australia/Sydney | AEST → |
| CHST | Chamorro Standard Time Oceania |
+10:00 | 09:25 ChST | Pacific/Guam | CHST → |
| ACDT | Australian Central Daylight Time Oceania |
+10:30 | 08:55 ACST | Australia/Adelaide | ACDT → |
| AEDT | Australian Eastern Daylight Time Oceania |
+11:00 | 09:25 AEST | Australia/Sydney | AEDT → |
| FJT | Fiji Time Oceania |
+12:00 | 11:25 UTC+12:00 | Pacific/Fiji | FJT → |
| NZST | New Zealand Standard Time Oceania |
+12:00 | 11:25 NZST | Pacific/Auckland | NZST → |
| NZDT | New Zealand Daylight Time Oceania |
+13:00 | 11:25 NZST | Pacific/Auckland | NZDT → |
The collisions in full
AST — 2 meanings
- Atlantic Standard Time
- America/Halifax
- Arabia Standard Time
- Asia/Riyadh
BST — 2 meanings
- British Summer Time
- Europe/London
- Bangladesh Standard Time
- Asia/Dhaka
CDT — 2 meanings
- Central Daylight Time
- America/Chicago
- Cuba Daylight Time
- America/Havana
CST — 3 meanings
- Central Standard Time
- America/Chicago
- China Standard Time
- Asia/Shanghai
- Cuba Standard Time
- America/Havana
EST — 2 meanings
- Eastern Standard Time
- America/New_York
- Eastern Standard Time (Australia)
- Australia/Sydney
GST — 2 meanings
- Gulf Standard Time
- Asia/Dubai
- South Georgia Time
- Atlantic/South_Georgia
IST — 3 meanings
- India Standard Time
- Asia/Kolkata
- Irish Standard Time
- Europe/Dublin
- Israel Standard Time
- Asia/Jerusalem
MST — 2 meanings
- Mountain Standard Time
- America/Denver
- Myanmar Standard Time
- Asia/Yangon
PST — 2 meanings
- Pacific Standard Time
- America/Los_Angeles
- Philippine Standard Time
- Asia/Manila
Questions
Are timezone abbreviations standardised?
No. There is no registry and no authority. CST alone means US Central Standard Time (UTC-6), China Standard Time (UTC+8) and Cuba Standard Time (UTC-5). Treat an abbreviation in incoming data as a hint that needs a human decision, never as a parseable offset.
What should I use instead in code?
IANA timezone names — America/New_York, Europe/London, Asia/Kolkata. They are stable identifiers maintained in the tz database, they carry the full history of offset and daylight-saving rule changes for that place, and every serious date library accepts them.
Why do some zones have two abbreviations?
Because they change clocks. The same place is EST in winter and EDT in summer, GMT and BST in the UK, CET and CEST across much of Europe. A meeting invite that says EST in July is nearly always a person meaning "Eastern time", not the literal UTC-5 offset.
Why is IST the most dangerous abbreviation?
Because its three meanings are all in active use and are hours apart: India Standard Time (UTC+5:30), Irish Standard Time (UTC+1 in summer) and Israel Standard Time (UTC+2). Search volume is dominated by India, which is exactly why an Irish or Israeli timestamp labelled IST gets silently misread.