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.

WIB to IRST

-3h 30m

WIB

WIBSOURCE

UTC+07:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

IRST

UTC+03:30

HH08

MM30

08:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

WIB

IRST

12:00 AM

8:30 PM-1

2:00 AM

10:30 PM-1

4:00 AM

12:30 AM

6:00 AM

2:30 AM

8:00 AM

4:30 AM

10:00 AM

6:30 AM

12:00 PM

8:30 AM

2:00 PM

10:30 AM

4:00 PM

12:30 PM

6:00 PM

2:30 PM

8:00 PM

4:30 PM

10:00 PM

6:30 PM

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

WIB and IRST on the World Map

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

WIB Zone

→

IRST Zone

Explore all world timezones interactively →

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

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 vs IRST: Offsets, DST and Best Call Times

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

In practice, when it is 9:00 AM in WIB it is 5:30 AM in IRST. Midnight in WIB is 8:30 PM in IRST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

WIB to IRST time conversion table

WIB (WIB)	IRST (IRST)	Day
12:00 AM	8:30 PM	previous day
6:00 AM	2:30 AM	same day
7:00 AM	3:30 AM	same day
8:00 AM	4:30 AM	same day
9:00 AM	5:30 AM	same day
12:00 PM	8:30 AM	same day
3:00 PM	11:30 AM	same day
5:00 PM	1:30 PM	same day
6:00 PM	2:30 PM	same day
9:00 PM	5:30 PM	same day

Why people convert WIB to IRST time

Scheduling a call from WIB to IRST: a 10:00 AM start in WIB lands at 6:30 AM in IRST, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both WIB and IRST are inside the 9-to-5 working day between 12:30 PM and 5:00 PM WIB time (9:00 AM–1:30 PM IRST). That is roughly 4 hours 30 minutes of usable overlap.
Keeping family and friends in sync: knowing that 8:00 PM in WIB is 4:30 PM in IRST makes it easy to avoid calling at 3 AM.

Always state the zone abbreviation, not just the hour. "3:00 PM WIB" is unambiguous; "3 PM" across a -3h 30m gap is not.
Block 12:30 PM–5:00 PM WIB as the recurring meeting window if you work primarily from WIB and need IRST colleagues present.

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.

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.

Best time to call between WIB and IRST

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

Business hours overlap

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

WIB is 3 hours 30 minutes behind IRST (WIB UTC+07:00 → IRST UTC+03:30). The shared working window is 12:30 PM–5:00 PM WIB. 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 WIB and IRST?

WIB (WIB, UTC+07:00) is 3 hours 30 minutes behind IRST (IRST, UTC+03:30). The gap is currently -3h 30m.

How do I convert WIB time to IRST time?

Add -3h 30m to WIB local time. For example, 9:00 AM in WIB is 5:30 AM in IRST.

What time is it in IRST right now?

IRST uses IRST at UTC+03:30. Use the live converter at the top of this page — it updates in real time and already accounts for the -3h 30m offset from WIB.