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 GST

+0h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

GST

UTC+04:00

HH12

MM30

12:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

GST

12:00 AM

12:30 AM

2:00 AM

2:30 AM

4:00 AM

4:30 AM

6:00 AM

6:30 AM

8:00 AM

8:30 AM

10:00 AM

10:30 AM

12:00 PM

12:30 PM

2:00 PM

2:30 PM

4:00 PM

4:30 PM

6:00 PM

6:30 PM

8:00 PM

8:30 PM

10:00 PM

10:30 PM

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

IRST and GST on the World Map

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

IRST Zone

→

GST 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

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

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 →

Tehran vs GST: Offsets, DST and Best Call Times

Tehran runs on Iran Standard Time (IRST) at UTC+03:30. GST runs on Gulf Standard Time (GST) at UTC+04:00. That puts Tehran 30 minutes ahead of GST — a difference of +0h 30m at the current offsets.

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

Tehran to GST time conversion table

Tehran (IRST)	GST (GST)	Day
12:00 AM	12:30 AM	same day
6:00 AM	6:30 AM	same day
7:00 AM	7:30 AM	same day
8:00 AM	8:30 AM	same day
9:00 AM	9:30 AM	same day
12:00 PM	12:30 PM	same day
3:00 PM	3:30 PM	same day
5:00 PM	5:30 PM	same day
6:00 PM	6:30 PM	same day
9:00 PM	9:30 PM	same day

Why people convert Tehran to GST time

Scheduling a call from Tehran to GST: a 10:00 AM start in Tehran lands at 10:30 AM in GST, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both Tehran and GST are inside the 9-to-5 working day between 9:00 AM and 4:30 PM IRST time (9:30 AM–5:00 PM GST). That is roughly 7 hours 30 minutes of usable overlap.
Coordinating a Tehran-based team with GST 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 +0h 30m gap is not.
Block 9:00 AM–4:30 PM IRST as the recurring meeting window if you work primarily from Tehran and need GST colleagues present.

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 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.

Best time to call between Tehran and GST

Both Tehran and GST sit inside the 9 AM – 5 PM working day between 9:00 AM–4:30 PM IRST, which is 9:30 AM–5:00 PM GST. That gives roughly 7 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

Tehran and GST share 7 hours of working-hours overlap (9:00 AM–4:30 PM IRST), so scheduling a live meeting is straightforward.

Tehran is 30 minutes ahead of GST (IRST UTC+03:30 → GST UTC+04:00). The shared working window is 9:00 AM–4:30 PM IRST. 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 GST?

Tehran (IRST, UTC+03:30) is 30 minutes ahead of GST (GST, UTC+04:00). The gap is currently +0h 30m.

How do I convert Tehran time to GST time?

Add +0h 30m to Tehran local time. For example, 9:00 AM in Tehran is 9:30 AM in GST.

What time is it in GST right now?

GST uses GST at UTC+04:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +0h 30m offset from Tehran.

What is the best time to call GST from Tehran?

Call between 9:00 AM and 4:30 PM IRST — that maps to 9:30 AM–5:00 PM GST and keeps both parties inside the working day.

Which is ahead, Tehran or GST?

Tehran is 30 minutes ahead of GST. When it is 12:00 PM in Tehran it is 12:30 PM in GST.

Do Tehran and GST use different time zones?

Tehran (Iran) uses IRST at UTC+03:30, while GST uses GST at UTC+04:00. The IANA identifiers are Asia/Tehran and Asia/Dubai.

Does daylight saving time affect the Tehran–GST difference?

Neither zone observes daylight saving time, so the +0h 30m offset between Tehran and GST 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 GST?

Not normally. The +0h 30m gap only pushes the date over for late-evening times.

What is the time difference between Tehran and GST?

GST is +0h 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.