Does it handle Daylight Saving Time?

Yes, the tool automatically adjusts for Daylight Saving Time based on the specific date you select, ensuring accurate conversions year-round.

Can I add multiple cities?

Yes, you can add as many cities as you need to the dashboard to compare times across your entire global network simultaneously.

Tehran to COT

-8h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

COT

UTC-05:00

HH03

MM30

03:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

COT

12:00 AM

3:30 PM-1

2:00 AM

5:30 PM-1

4:00 AM

7:30 PM-1

6:00 AM

9:30 PM-1

8:00 AM

11:30 PM-1

10:00 AM

1:30 AM

12:00 PM

3:30 AM

2:00 PM

5:30 AM

4:00 PM

7:30 AM

6:00 PM

9:30 AM

8:00 PM

11:30 AM

10:00 PM

1:30 PM

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

IRST and COT on the World Map

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

IRST Zone

→

COT Zone

Explore all world timezones interactively →

IRST – Iran Standard Time

UTC+03:30

Iran Standard Time (IRST) is the time zone for Iran, 3 hours and 30 minutes ahead of UTC.

Countries in IRST

Iran

Major Cities in IRST

TehranIsfahanMashhadTabrizShirazKaraj

Key Facts about IRST

•IRST is one of only a few time zones with a 30-minute offset.
•Iran observes daylight saving time, switching to IRDT (UTC+04:30).
•Tehran has a metropolitan population of over 16 million.

Daylight Saving:Yes – switches to IRDT

Learn more about IRST 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

About Tehran

Wikipedia

Tehran operates on Iran Standard Time (IRST), UTC+3:30. Iran's unique half-hour offset makes Tehran time distinctive for regional business coordination.

Population:9.4 million

Metro:16.8 million

Business Hours:8:00 AM - 4:00 PM IRST

Currency:IRR (﷼)

Stock Exchange:TSE (Tehran Stock Exchange)

Key Landmarks

Azadi TowerGolestan PalaceGrand BazaarMilad TowerTabiat Bridge

Did You Know?

Iran Standard Time (IRST) is one of few timezones with a 30-minute offset (UTC+3:30).

Learn more about IRST timezone →

Time Conversion Guide: Tehran to COT

Tehran runs on Iran Standard Time (IRST) at UTC+03:30. COT runs on Colombia Time (COT) at UTC-05:00. That puts Tehran 8 hours 30 minutes behind COT — a difference of -8h 30m at the current offsets.

In practice, when it is 9:00 AM in Tehran it is 12:30 AM in COT. Midnight in Tehran is 3:30 PM in COT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Tehran to COT time conversion table

Tehran (IRST)	COT (COT)	Day
12:00 AM	3:30 PM	previous day
6:00 AM	9:30 PM	previous day
7:00 AM	10:30 PM	previous day
8:00 AM	11:30 PM	previous day
9:00 AM	12:30 AM	same day
12:00 PM	3:30 AM	same day
3:00 PM	6:30 AM	same day
5:00 PM	8:30 AM	same day
6:00 PM	9:30 AM	same day
9:00 PM	12:30 PM	same day

Why people convert Tehran to COT time

Scheduling a call from Tehran to COT: a 10:00 AM start in Tehran lands at 1:30 AM in COT, so you can confirm the slot without doing the arithmetic yourself.
Handling a -8h 30m gap: Tehran 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 12:30 AM in Tehran.
Coordinating a Tehran-based team with COT contacts: quoting times in the other side's local clock — not your own — removes the single biggest source of missed meetings.

Always state the zone abbreviation, not just the hour. "3:00 PM IRST" is unambiguous; "3 PM" across a -8h 30m gap is not.
With a -8h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week Tehran takes the early slot, the next week COT does.

About IRST (Iran Standard Time)

Iran Standard Time (IRST) is one of the few time zones with a 30-minute offset. Iran observes daylight saving time (IRDT, UTC+04:30) from late March to late September. Tehran, the capital, is one of the largest cities in the Middle East.

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 Tehran and COT

With a -8h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. COT opens at 9:00 AM COT, which is 12:30 AM in Tehran, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Tehran and COT have no shared working hours because of the -8h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.

Tehran is 8 hours 30 minutes behind COT (IRST UTC+03:30 → 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.

Learn More About Time

Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:

⏳

History of Timekeeping

From sundials to atomic clocks - 5000 years of measuring time

🌍

How Time Zones Work

UTC, offsets, and why zones don't follow straight lines

☀️

Daylight Saving Time

DST dates, which countries observe it, and the ongoing debate

Frequently Asked Questions

What is the time difference between Tehran and COT?

Tehran (IRST, UTC+03:30) is 8 hours 30 minutes behind COT (COT, UTC-05:00). The gap is currently -8h 30m.

How do I convert Tehran time to COT time?

Add -8h 30m to Tehran local time. For example, 9:00 AM in Tehran is 12:30 AM in COT.

What time is it in COT right now?

COT uses COT at UTC-05:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -8h 30m offset from Tehran.

What is the best time to call COT from Tehran?

There is no shared working-hours window because of the -8h 30m gap. The closest option is 1:00 PM in Tehran, which is 4:30 AM in COT.

Which is behind, Tehran or COT?

Tehran is 8 hours 30 minutes behind COT. When it is 12:00 PM in Tehran it is 3:30 AM in COT.

Do Tehran and COT use different time zones?

Tehran (Iran) uses IRST at UTC+03:30, while COT uses COT at UTC-05:00. The IANA identifiers are Asia/Tehran and America/Bogota.

Does daylight saving time affect the Tehran–COT difference?

Neither zone observes daylight saving time, so the -8h 30m offset between Tehran and COT is fixed all year.

Which other cities share Tehran's time zone?

IRST also covers Tehran, Isfahan, Mashhad, Tabriz, Shiraz, Karaj.

Which countries use IRST, Tehran's zone?

IRST is used in Iran.

Is there a day difference between Tehran and COT?

Not normally. The -8h 30m gap only pushes the date over the previous day.

What is the time difference between Tehran and COT?

COT is -8h 30m from Tehran.

What timezone is Tehran in?

Tehran operates on Iran Standard Time (IRST), UTC+3:30. Iran's unique half-hour offset makes Tehran time distinctive for regional business coordination.