Time zone abbreviations
What each abbreviation means on this site, its offset from UTC in winter and summer (2026), and the ones that are ambiguous. You can type any of them into the converter.
Abbreviations with more than one meaning
Time zone abbreviations aren't an official standard, and several are shared. When you type one of these, the converter lists every meaning; the first one is what the conversion pages on this site use.
| Abbreviation | Meanings (first = used here) |
|---|---|
CST | CST can mean US Central Standard Time (UTC−6) or China Standard Time (UTC+8). Cuba also uses CST. Used here: Central Time (US). |
IST | IST can mean India Standard Time (UTC+5:30), Israel Standard Time (UTC+2) or Irish Standard Time (Ireland in summer, UTC+1). Used here: India Standard Time. |
AST | AST can mean Atlantic Standard Time (UTC−4, Halifax, Puerto Rico) or Arabia Standard Time (UTC+3, Riyadh). Used here: Atlantic Time (Canada). |
PST | PST almost always means US Pacific Time, but the Philippines also calls its time Philippine Standard Time (UTC+8). Used here: Pacific Time (US). |
BST | BST is British Summer Time (UTC+1). Bangladesh Standard Time is also abbreviated BST; for that, pick Dhaka. Used here: UK Time (GMT / BST). |
GST | GST usually means Gulf Standard Time (UTC+4, Dubai). South Georgia Time also uses GST. Used here: Gulf Standard Time. |
All abbreviations
| Zone | Abbreviation | Offset (winter / summer) |
|---|---|---|
| Eastern Time (US) EST / EDT, follows New York CST to EST, PST to EST, UTC to EST, EST to CST | EST / EDT | UTC−5 / UTC−4 |
| Central Time (US) CST / CDT, follows Chicago CST to EST, EST to CST, PST to CST, UTC to CST | CST / CDT | UTC−6 / UTC−5 |
| Mountain Time (US) MST / MDT, follows Denver MST to EST, PST to MST, MST to PST, EST to MST | MST / MDT | UTC−7 / UTC−6 |
| Arizona Time MST all year, no daylight saving Arizona to EST | MST | UTC−7 |
| Pacific Time (US) PST / PDT, follows Los Angeles PST to EST, PST to CST, UTC to PST, EST to PST | PST / PDT | UTC−8 / UTC−7 |
| Alaska Time AKST / AKDT, follows Anchorage | AKST / AKDT | UTC−9 / UTC−8 |
| Hawaii Time HST all year EST to HST, HST to EST, PST to HST, HST to PST | HST | UTC−10 |
| Atlantic Time (Canada) AST / ADT, follows Halifax | AST / ADT | UTC−4 / UTC−3 |
| Newfoundland Time NST / NDT, UTC−3:30 in winter | NST / NDT | UTC−3:30 / UTC−2:30 |
| UTC Coordinated Universal Time, never changes UTC to EST, UTC to PST, UTC to CST, EST to UTC | UTC | UTC |
| GMT Greenwich Mean Time, UTC+0, never changes GMT to EST, GMT to CST, EST to GMT, GMT to PST | GMT | UTC |
| UK Time (GMT / BST) GMT in winter, BST in summer BST to EST, BST to PST | GMT / BST | UTC / UTC+1 |
| Irish Time GMT in winter, IST (Irish Standard Time) in summer | GMT / IST | UTC / UTC+1 |
| Western European Time WET / WEST, follows Lisbon | WET / WEST | UTC / UTC+1 |
| Central European Time CET / CEST, follows Paris and Berlin CET to EST, CET to PST, PST to CET, CET to CST | CET / CEST | UTC+1 / UTC+2 |
| Eastern European Time EET / EEST, follows Athens | EET / EEST | UTC+2 / UTC+3 |
| Moscow Time MSK, UTC+3 all year | MSK | UTC+3 |
| South Africa Time SAST, UTC+2 all year | SAST | UTC+2 |
| West Africa Time WAT, UTC+1 all year | WAT | UTC+1 |
| East Africa Time EAT, UTC+3 all year | EAT | UTC+3 |
| Israel Time IST / IDT, follows Jerusalem | IST / IDT | UTC+2 / UTC+3 |
| Arabia Standard Time AST, UTC+3 all year, follows Riyadh | AST | UTC+3 |
| Gulf Standard Time GST, UTC+4 all year, follows Dubai | GST | UTC+4 |
| Pakistan Time PKT, UTC+5 all year | PKT | UTC+5 |
| India Standard Time IST, UTC+5:30 all year EST to IST, IST to EST, CST to IST, PST to IST | IST | UTC+5:30 |
| Nepal Time NPT, UTC+5:45 all year | NPT | UTC+5:45 |
| Indochina Time ICT, UTC+7, follows Bangkok | ICT | UTC+7 |
| China Standard Time CST, UTC+8 all year, follows Beijing | CST | UTC+8 |
| Hong Kong Time HKT, UTC+8 all year | HKT | UTC+8 |
| Singapore Time SGT, UTC+8 all year | SGT | UTC+8 |
| Philippine Time PHT (also written PST), UTC+8 all year | PHT | UTC+8 |
| Korea Standard Time KST, UTC+9 all year KST to EST | KST | UTC+9 |
| Japan Standard Time JST, UTC+9 all year JST to EST, JST to PST, EST to JST, PST to JST | JST | UTC+9 |
| Australian Western Time AWST, UTC+8, follows Perth | AWST | UTC+8 |
| Australian Central Time ACST / ACDT, follows Adelaide | ACST / ACDT | UTC+9:30 / UTC+10:30 |
| Australian Eastern Time AEST / AEDT, follows Sydney EST to AEST, AEST to EST | AEST / AEDT | UTC+10 / UTC+11 |
| New Zealand Time NZST / NZDT, follows Auckland | NZST / NZDT | UTC+12 / UTC+13 |
Offsets are computed from the IANA time zone database for January and July 2026. "Winter / summer" follows the northern-hemisphere seasons for northern zones; for Australia and New Zealand the larger offset applies in their summer (around October to April).
Questions
Is UTC the same as GMT?
For clock times, yes: both are UTC+0 and neither has daylight saving. UTC is the scientific time standard; GMT is the name of the zone. The UK only uses GMT in winter and switches to BST (UTC+1) in summer, so "GMT" and "the time in London" are different for about seven months a year.
What does the D in EDT, CDT and PDT mean?
Daylight. EDT, CDT, MDT and PDT are the summer (daylight saving) versions of EST, CST, MST and PST, each one hour ahead of the standard version. The S stands for standard, which is winter time.
Why do people write EST in summer?
Out of habit. Strictly, the US East Coast is on EDT in summer, but "EST" is widely used to mean Eastern Time all year. This site treats EST, CST, MST and PST as the regions, and uses the correct offset for the date.