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 COT

-9h

GST

GSTSOURCE

UTC+04:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

COT

UTC-05:00

HH03

MM00

03:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

GST

COT

12:00 AM

3:00 PM-1

2:00 AM

5:00 PM-1

4:00 AM

7:00 PM-1

6:00 AM

9:00 PM-1

8:00 AM

11:00 PM-1

10:00 AM

1:00 AM

12:00 PM

3:00 AM

2:00 PM

5:00 AM

4:00 PM

7:00 AM

6:00 PM

9:00 AM

8:00 PM

11:00 AM

10:00 PM

1:00 PM

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

GST and COT on the World Map

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

GST Zone

→

COT 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

COT – Colombia Time

UTC-05:00

Colombia Time (COT) is the standard time for Colombia, 5 hours behind UTC.

Countries in COT

Colombia

Major Cities in COT

BogotáMedellínCaliBarranquillaCartagena

Key Facts about COT

•Colombia does not observe daylight saving time.
•COT is the same offset as EST (UTC-05:00).
•Bogotá sits at 2,640m elevation, making it one of the highest capital cities.

Daylight Saving:No – UTC-05:00 year-round

Learn more about COT on Wikipedia

Understanding the -9h Gap: GST vs COT

GST runs on Gulf Standard Time (GST) at UTC+04:00. COT runs on Colombia Time (COT) at UTC-05:00. That puts GST 9 hours behind COT — a difference of -9h at the current offsets.

In practice, when it is 9:00 AM in GST it is 12:00 AM in COT. Midnight in GST is 3:00 PM in COT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

GST to COT time conversion table

GST (GST)	COT (COT)	Day
12:00 AM	3:00 PM	previous day
6:00 AM	9:00 PM	previous day
7:00 AM	10:00 PM	previous day
8:00 AM	11:00 PM	previous day
9:00 AM	12:00 AM	same day
12:00 PM	3:00 AM	same day
3:00 PM	6:00 AM	same day
5:00 PM	8:00 AM	same day
6:00 PM	9:00 AM	same day
9:00 PM	12:00 PM	same day

Why people convert GST to COT time

Scheduling a call from GST to COT: a 10:00 AM start in GST lands at 1:00 AM in COT, so you can confirm the slot without doing the arithmetic yourself.
Handling a -9h gap: GST and COT have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in COT is 12:00 AM in GST.
Keeping family and friends in sync: knowing that 8:00 PM in GST is 11:00 AM in COT makes it easy to avoid calling at 3 AM.

Always state the zone abbreviation, not just the hour. "3:00 PM GST" is unambiguous; "3 PM" across a -9h gap is not.
With a -9h gap there is no shared 9-to-5 window, so alternate the early start: one week GST takes the early slot, the next week COT does.

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 COT (Colombia Time)

Colombia Time (COT) is used throughout Colombia. Colombia does not observe daylight saving time. COT shares the same offset as EST (UTC-05:00). Bogotá, the capital, is one of the largest cities in South America.

Best time to call between GST and COT

With a -9h offset there is no overlap inside a normal 9 AM – 5 PM day. COT opens at 9:00 AM COT, which is 12:00 AM in GST, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

GST and COT have no shared working hours because of the -9h gap. Teams need to alternate early starts or rely on asynchronous handovers.

GST is 9 hours behind COT (GST UTC+04:00 → COT UTC-05:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.