Does it account for Daylight Saving Time?

Yes, our converter uses the IANA timezone database, which includes all current DST rules for every timezone in the world.

UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks. All timezones are defined as offsets from UTC.

Can I compare multiple timezones at once?

Yes, you can add multiple cities or timezones and see the equivalent times side by side.

How many timezones are there in the world?

There are 38 distinct UTC offsets in use, ranging from UTC-12 to UTC+14. This includes half-hour (UTC+5:30 India, UTC+9:30 Australia) and 45-minute offsets (UTC+5:45 Nepal, UTC+8:45 Australia).

What is the International Date Line?

The International Date Line (IDL) runs roughly along the 180° meridian in the Pacific Ocean. When you cross it westward, you gain a day; crossing eastward, you lose a day.

Why do some timezones have 30 or 45 minute offsets?

Countries chose offsets that best matched their solar noon. India uses UTC+5:30 and Nepal uses UTC+5:45 because standard hourly offsets didn't align well with their geography.

Which country has the most timezones?

France has the most (12 timezones) due to overseas territories. Russia spans 11 timezones. The US has 6 (including Hawaii and Alaska).

GST to TRT

-1h

GST

GSTSOURCE

UTC+04:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

TRT

UTC+03:00

HH11

MM00

11:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

GST

TRT

12:00 AM

11:00 PM-1

2:00 AM

1:00 AM

4:00 AM

3:00 AM

6:00 AM

5:00 AM

8:00 AM

7:00 AM

10:00 AM

9:00 AM

12:00 PM

11:00 AM

2:00 PM

1:00 PM

4:00 PM

3:00 PM

6:00 PM

5:00 PM

8:00 PM

7:00 PM

10:00 PM

9:00 PM

Green rows indicate typical business hours (9 AM - 5 PM)

GST and TRT on the World Map

The map below highlights the GST (Gulf Standard Time) and TRT (Turkey Time) timezone regions across the globe.

GST Zone

→

TRT Zone

Explore all world timezones interactively →

GST – Gulf Standard Time

UTC+04:00

Gulf Standard Time (GST) is used in the UAE, Oman, and other Gulf states, 4 hours ahead of UTC.

Countries in GST

UAEOmanGeorgiaAzerbaijanMauritius

Major Cities in GST

DubaiAbu DhabiMuscatBakuTbilisi

Key Facts about GST

•Dubai uses GST year-round with no daylight saving time.
•GST is 9 hours ahead of EST and 4 hours ahead of GMT.
•The Dubai Financial Market (DFM) operates on GST.

Daylight Saving:No – UTC+04:00 year-round

Learn more about GST on Wikipedia

TRT – Turkey Time

UTC+03:00

Turkey Time (TRT, UTC+03:00) is the single time zone used across Turkey, fixed year round since 2016.

Countries in TRT

Turkey

Major Cities in TRT

IstanbulAnkaraIzmirBursaAntalya

Key Facts about TRT

•Turkey has used a permanent UTC+03:00 since September 2016.
•TRT is level with Moscow Standard Time and Arabia Standard Time all year.
•Because Turkey kept summer time permanently, western cities see very late winter sunrises.
•Turkey previously observed daylight saving time from 1973 to 2016.

Daylight Saving:No – UTC+03:00 year-round

Learn more about TRT on Wikipedia

Understanding the -1h Gap: GST vs TRT

GST runs on Gulf Standard Time (GST) at UTC+04:00. TRT runs on Turkey Time (TRT) at UTC+03:00. That puts GST 1 hour behind TRT — a difference of -1h at the current offsets.

In practice, when it is 9:00 AM in GST it is 8:00 AM in TRT. Midnight in GST is 11:00 PM in TRT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

GST to TRT time conversion table

GST (GST)	TRT (TRT)	Day
12:00 AM	11:00 PM	previous day
6:00 AM	5:00 AM	same day
7:00 AM	6:00 AM	same day
8:00 AM	7:00 AM	same day
9:00 AM	8:00 AM	same day
12:00 PM	11:00 AM	same day
3:00 PM	2:00 PM	same day
5:00 PM	4:00 PM	same day
6:00 PM	5:00 PM	same day
9:00 PM	8:00 PM	same day

Why people convert GST to TRT time

Scheduling a call from GST to TRT: a 10:00 AM start in GST lands at 9:00 AM in TRT, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both GST and TRT are inside the 9-to-5 working day between 10:00 AM and 5:00 PM GST time (9:00 AM–4:00 PM TRT). That is roughly 7 hours of usable overlap.
Watching a live event or market open: GST viewers need 8:00 AM in TRT to catch a 9:00 AM start there, and 1:00 AM if the event is anchored to GST.

Always state the zone abbreviation, not just the hour. "3:00 PM GST" is unambiguous; "3 PM" across a -1h gap is not.
Block 10:00 AM–5:00 PM GST as the recurring meeting window if you work primarily from GST and need TRT colleagues present.

About GST (Gulf Standard Time)

Gulf Standard Time (GST) is the time zone used in the United Arab Emirates, Oman, and other Gulf states. GST does not observe daylight saving time. Dubai and Abu Dhabi, major international business and tourism hubs, operate on GST.

About TRT (Turkey Time)

Turkey Time (TRT) is fixed at UTC+03:00 all year. Turkey abolished seasonal clock changes in September 2016, moving to a permanent UTC+03:00 so the whole country stays on what was formerly summer time. That leaves Istanbul, which sits close to 29°E, on an offset well ahead of its solar time — sunrise in mid-winter comes after 08:30 local. TRT shares its offset with Moscow Standard Time, Arabia Standard Time and East Africa Time, so Istanbul is level with Moscow and Riyadh all year and one hour ahead of Central European Time during the European winter.

Best time to call between GST and TRT

Both GST and TRT sit inside the 9 AM – 5 PM working day between 10:00 AM–5:00 PM GST, which is 9:00 AM–4:00 PM TRT. That gives roughly 7 hours of shared time — the safest window for a live call or meeting.

Business hours overlap

GST and TRT share 7 hours of working-hours overlap (10:00 AM–5:00 PM GST), so scheduling a live meeting is straightforward.

GST is 1 hour behind TRT (GST UTC+04:00 → TRT UTC+03:00). The shared working window is 10:00 AM–5:00 PM GST. Remember to re-check around daylight-saving transitions.