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.

IRST to Ho Chi Minh

+3h 30m

IRST

IRSTSOURCE

UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Ho Chi Minh

ICT

Vietnam · UTC+07:00

HH03

MM30

15:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

IRST

Ho Chi Minh

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 ICT on the World Map

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

IRST Zone

→

ICT 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

ICT – Indochina Time

UTC+07:00

Indochina Time (ICT) is the time zone for Vietnam, Thailand, Laos, and Cambodia, 7 hours ahead of UTC.

Countries in ICT

ThailandVietnamCambodiaLaosIndonesia (WIB)

Major Cities in ICT

BangkokHo Chi Minh CityHanoiJakartaPhnom PenhVientiane

Key Facts about ICT

•Bangkok is one of the most visited cities in the world.
•ICT is 12 hours ahead of EST.
•Thailand, Vietnam, and Cambodia all share ICT.

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

Learn more about ICT on Wikipedia

About Ho Chi Minh

Wikipedia

Ho Chi Minh City operates on Indochina Time (ICT), UTC+7. As Vietnam's economic powerhouse and a manufacturing hub, Saigon drives Southeast Asian trade.

Population:9 million

Metro:13 million

Business Hours:8:00 AM - 5:00 PM ICT

Currency:VND (₫)

Stock Exchange:HOSE (Ho Chi Minh Stock Exchange)

Key Landmarks

Notre-Dame CathedralWar Remnants MuseumBen Thanh MarketIndependence PalaceCu Chi Tunnels

Did You Know?

The city has over 5 million motorbikes, outnumbering cars significantly.

Learn more about ICT timezone →

Everything You Need to Know About IRST and Ho Chi Minh Time

IRST runs on Iran Standard Time (IRST) at UTC+03:30. Ho Chi Minh runs on Indochina Time (ICT) at UTC+07:00. That puts IRST 3 hours 30 minutes ahead of Ho Chi Minh — a difference of +3h 30m at the current offsets.

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

IRST to Ho Chi Minh time conversion table

IRST (IRST)	Ho Chi Minh (ICT)	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 IRST to Ho Chi Minh time

Scheduling a call from IRST to Ho Chi Minh: a 10:00 AM start in IRST lands at 1:30 PM in Ho Chi Minh, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both IRST and Ho Chi Minh are inside the 9-to-5 working day between 9:00 AM and 1:30 PM IRST time (12:30 PM–5:00 PM ICT). That is roughly 4 hours 30 minutes of usable overlap.
Booking travel or deliveries: tracking Ho Chi Minh local time against IRST keeps pickup windows and arrival estimates honest across the +3h 30m offset.

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 IRST and need Ho Chi Minh 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 ICT (Indochina Time)

Indochina Time (ICT) is used across Southeast Asia including Vietnam, Thailand, Laos, and Cambodia. Indonesia (Western time, WIB) also uses UTC+07:00. ICT does not observe daylight saving time.

Best time to call between IRST and Ho Chi Minh

Both IRST and Ho Chi Minh 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 ICT. That gives roughly 4 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

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

IRST is 3 hours 30 minutes ahead of Ho Chi Minh (IRST UTC+03:30 → ICT 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 IRST and Ho Chi Minh?

IRST (IRST, UTC+03:30) is 3 hours 30 minutes ahead of Ho Chi Minh (ICT, UTC+07:00). The gap is currently +3h 30m.

How do I convert IRST time to Ho Chi Minh time?

Add +3h 30m to IRST local time. For example, 9:00 AM in IRST is 12:30 PM in Ho Chi Minh.

What time is it in Ho Chi Minh right now?

Ho Chi Minh uses ICT 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 IRST.

What is the best time to call Ho Chi Minh from IRST?

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

Which is ahead, IRST or Ho Chi Minh?

IRST is 3 hours 30 minutes ahead of Ho Chi Minh. When it is 12:00 PM in IRST it is 3:30 PM in Ho Chi Minh.

Do IRST and Ho Chi Minh use different time zones?

IRST uses IRST at UTC+03:30, while Ho Chi Minh (Vietnam) uses ICT at UTC+07:00. The IANA identifiers are Asia/Tehran and Asia/Ho_Chi_Minh.

Does daylight saving time affect the IRST–Ho Chi Minh difference?

Neither zone observes daylight saving time, so the +3h 30m offset between IRST and Ho Chi Minh is fixed all year.

Which other cities share IRST's time zone?

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

Which countries use IRST, IRST's zone?

IRST is used in Iran.

Is there a day difference between IRST and Ho Chi Minh?

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

What is the time difference between IRST and Ho Chi Minh?

Ho Chi Minh is +3h 30m from IRST.

What timezone is IRST in?

IRST operates on its local timezone.

What timezone is Ho Chi Minh in?

Ho Chi Minh City operates on Indochina Time (ICT), UTC+7. As Vietnam's economic powerhouse and a manufacturing hub, Saigon drives Southeast Asian trade.