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).

Tehran to Indonesia

+3h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Indonesia

WIB

UTC+07:00

HH03

MM30

15:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

Indonesia

12:00 AM

3:30 AM

2:00 AM

5:30 AM

4:00 AM

7:30 AM

6:00 AM

9:30 AM

8:00 AM

11:30 AM

10:00 AM

1:30 PM

12:00 PM

3:30 PM

2:00 PM

5:30 PM

4:00 PM

7:30 PM

6:00 PM

9:30 PM

8:00 PM

11:30 PM

10:00 PM

1:30 AM+1

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

IRST and WIB on the World Map

The map below highlights the IRST (Iran Standard Time) and WIB (Western Indonesia Time) timezone regions across the globe.

IRST Zone

→

WIB 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

WIB – Western Indonesia Time

UTC+07:00

Western Indonesia Time (WIB, UTC+07:00) covers Java, Sumatra and West Kalimantan, including Jakarta.

Countries in WIB

Indonesia (Java, Sumatra, West Kalimantan)

Major Cities in WIB

JakartaSurabayaBandungMedanPalembang

Key Facts about WIB

•Indonesia spans three time zones: WIB (UTC+07:00), WITA (UTC+08:00) and WIT (UTC+09:00).
•Indonesia has not observed daylight saving time since 1964.
•Jakarta is the largest city in Southeast Asia by population.
•WIB shares the UTC+07:00 offset with Indochina Time.

Daylight Saving:No – UTC+07:00 year-round

Learn more about WIB 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 Indonesia

Tehran runs on Iran Standard Time (IRST) at UTC+03:30. Indonesia runs on Western Indonesia Time (WIB) at UTC+07:00. That puts Tehran 3 hours 30 minutes ahead of Indonesia — a difference of +3h 30m at the current offsets.

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

Tehran to Indonesia time conversion table

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

Why people convert Tehran to Indonesia time

Scheduling a call from Tehran to Indonesia: a 10:00 AM start in Tehran lands at 1:30 PM in Indonesia, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both Tehran and Indonesia are inside the 9-to-5 working day between 9:00 AM and 1:30 PM IRST time (12:30 PM–5:00 PM WIB). That is roughly 4 hours 30 minutes of usable overlap.
Watching a live event or market open: Tehran viewers need 12:30 PM in Indonesia to catch a 9:00 AM start there, and 8:30 PM if the event is anchored to Tehran.

Always state the zone abbreviation, not just the hour. "3:00 PM IRST" is unambiguous; "3 PM" across a +3h 30m gap is not.
Block 9:00 AM–1:30 PM IRST as the recurring meeting window if you work primarily from Tehran and need Indonesia 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 WIB (Western Indonesia Time)

Western Indonesia Time (WIB, Waktu Indonesia Barat) is one of Indonesia's three time zones, fixed at UTC+07:00 all year. It covers Java, Sumatra, West Kalimantan and the provinces around them — home to Jakarta, the country's capital and largest city, plus Surabaya and Bandung. Indonesia does not observe daylight saving time, so WIB never shifts. WIB shares its UTC+07:00 offset with Indochina Time (ICT) and Christmas Island Time, but is a distinct zone covering the western half of the Indonesian archipelago. The country's other zones are WITA (UTC+08:00) in the centre and WIT (UTC+09:00) in the east.

Best time to call between Tehran and Indonesia

Both Tehran and Indonesia sit inside the 9 AM – 5 PM working day between 9:00 AM–1:30 PM IRST, which is 12:30 PM–5:00 PM WIB. That gives roughly 4 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

Tehran and Indonesia overlap for about 4 hours during the working day — enough for meetings if you avoid the edges of the window.

Tehran is 3 hours 30 minutes ahead of Indonesia (IRST UTC+03:30 → WIB UTC+07:00). The shared working window is 9:00 AM–1:30 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 Indonesia?

Tehran (IRST, UTC+03:30) is 3 hours 30 minutes ahead of Indonesia (WIB, UTC+07:00). The gap is currently +3h 30m.

How do I convert Tehran time to Indonesia time?

Add +3h 30m to Tehran local time. For example, 9:00 AM in Tehran is 12:30 PM in Indonesia.

What time is it in Indonesia right now?

Indonesia uses WIB at UTC+07:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +3h 30m offset from Tehran.

What is the best time to call Indonesia from Tehran?

Call between 9:00 AM and 1:30 PM IRST — that maps to 12:30 PM–5:00 PM WIB and keeps both parties inside the working day.

Which is ahead, Tehran or Indonesia?

Tehran is 3 hours 30 minutes ahead of Indonesia. When it is 12:00 PM in Tehran it is 3:30 PM in Indonesia.

Do Tehran and Indonesia use different time zones?

Tehran (Iran) uses IRST at UTC+03:30, while Indonesia (Indonesia) uses WIB at UTC+07:00. The IANA identifiers are Asia/Tehran and Asia/Jakarta.

Does daylight saving time affect the Tehran–Indonesia difference?

Neither zone observes daylight saving time, so the +3h 30m offset between Tehran and Indonesia 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 Indonesia?

Not normally. The +3h 30m gap only pushes the date over for late-evening times.

What is the time difference between Tehran and Indonesia?

Indonesia is +3h 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.