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 Singapore

+4h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Singapore

SGT

Singapore · UTC+08:00

HH04

MM30

16:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

Singapore

12:00 AM

4:30 AM

2:00 AM

6:30 AM

4:00 AM

8:30 AM

6:00 AM

10:30 AM

8:00 AM

12:30 PM

10:00 AM

2:30 PM

12:00 PM

4:30 PM

2:00 PM

6:30 PM

4:00 PM

8:30 PM

6:00 PM

10:30 PM

8:00 PM

12:30 AM+1

10:00 PM

2:30 AM+1

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

IRST and SGT on the World Map

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

IRST Zone

→

SGT 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

SGT – Singapore Standard Time

UTC+08:00

Singapore Standard Time (SGT) is the time zone for Singapore, 8 hours ahead of UTC.

Countries in SGT

Singapore

Major Cities in SGT

Singapore

Key Facts about SGT

•Singapore uses UTC+08:00 despite being at about 104°E longitude (closer to UTC+07:00).
•Singapore does not observe daylight saving time.
•The Singapore Exchange (SGX) operates on SGT.

Daylight Saving:No – UTC+08:00 year-round

Learn more about SGT 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 →

About Singapore

Wikipedia

Singapore Standard Time (SGT) is 8 hours ahead of GMT. As Asia's leading financial hub, Singapore bridges business hours between Europe and Australia.

Population:5.5 million

Metro:5.9 million

Business Hours:9:00 AM - 6:00 PM SGT

Currency:SGD (S$)

Stock Exchange:SGX (Singapore Exchange)

Key Landmarks

Marina Bay SandsGardens by the BayMerlionSentosa IslandOrchard Road

Did You Know?

The city-state has the world's highest percentage of millionaires, with 1 in 6 households.

Learn more about SGT timezone →

Tehran vs Singapore: Offsets, DST and Best Call Times

Tehran runs on Iran Standard Time (IRST) at UTC+03:30. Singapore runs on Singapore Standard Time (SGT) at UTC+08:00. That puts Tehran 4 hours 30 minutes ahead of Singapore — a difference of +4h 30m at the current offsets.

In practice, when it is 9:00 AM in Tehran it is 1:30 PM in Singapore. Midnight in Tehran is 4:30 AM in Singapore. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Tehran to Singapore time conversion table

Tehran (IRST)	Singapore (SGT)	Day
12:00 AM	4:30 AM	same day
6:00 AM	10:30 AM	same day
7:00 AM	11:30 AM	same day
8:00 AM	12:30 PM	same day
9:00 AM	1:30 PM	same day
12:00 PM	4:30 PM	same day
3:00 PM	7:30 PM	same day
5:00 PM	9:30 PM	same day
6:00 PM	10:30 PM	same day
9:00 PM	1:30 AM	next day

Why people convert Tehran to Singapore time

Scheduling a call from Tehran to Singapore: a 10:00 AM start in Tehran lands at 2:30 PM in Singapore, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both Tehran and Singapore are inside the 9-to-5 working day between 9:00 AM and 12:30 PM IRST time (1:30 PM–5:00 PM SGT). That is roughly 3 hours 30 minutes of usable overlap.
Coordinating a Tehran-based team with Singapore 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 +4h 30m gap is not.
Block 9:00 AM–12:30 PM IRST as the recurring meeting window if you work primarily from Tehran and need Singapore 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 SGT (Singapore Standard Time)

Singapore Standard Time (SGT) is used in Singapore year-round. Singapore does not observe daylight saving time. Despite being geographically close to the UTC+07:00 zone, Singapore uses UTC+08:00 to align with major trading partners like China, Hong Kong, and Malaysia. Singapore is a major global financial hub.

Best time to call between Tehran and Singapore

Both Tehran and Singapore sit inside the 9 AM – 5 PM working day between 9:00 AM–12:30 PM IRST, which is 1:30 PM–5:00 PM SGT. That gives roughly 3 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

Tehran and Singapore overlap for about 3 hours during the working day — enough for meetings if you avoid the edges of the window.

Tehran is 4 hours 30 minutes ahead of Singapore (IRST UTC+03:30 → SGT UTC+08:00). The shared working window is 9:00 AM–12:30 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 Singapore?

Tehran (IRST, UTC+03:30) is 4 hours 30 minutes ahead of Singapore (SGT, UTC+08:00). The gap is currently +4h 30m.

How do I convert Tehran time to Singapore time?

Add +4h 30m to Tehran local time. For example, 9:00 AM in Tehran is 1:30 PM in Singapore.

What time is it in Singapore right now?

Singapore uses SGT at UTC+08:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +4h 30m offset from Tehran.

What is the best time to call Singapore from Tehran?

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

Which is ahead, Tehran or Singapore?

Tehran is 4 hours 30 minutes ahead of Singapore. When it is 12:00 PM in Tehran it is 4:30 PM in Singapore.

Do Tehran and Singapore use different time zones?

Tehran (Iran) uses IRST at UTC+03:30, while Singapore (Singapore) uses SGT at UTC+08:00. The IANA identifiers are Asia/Tehran and Asia/Singapore.

Does daylight saving time affect the Tehran–Singapore difference?

Neither zone observes daylight saving time, so the +4h 30m offset between Tehran and Singapore 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 Singapore?

Not normally. The +4h 30m gap only pushes the date over for late-evening times.

What is the time difference between Tehran and Singapore?

Singapore is +4h 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.

What timezone is Singapore in?

Singapore Standard Time (SGT) is 8 hours ahead of GMT. As Asia's leading financial hub, Singapore bridges business hours between Europe and Australia.

What are the business hours in Tehran?

Standard business hours in Tehran are 8:00 AM - 4:00 PM IRST.

What are the business hours in Singapore?

Standard business hours in Singapore are 9:00 AM - 6:00 PM SGT.

What is the best time to schedule a call between Tehran and Singapore?

The best overlap for a call is when both cities are in business hours. Tehran works 8:00 AM - 4:00 PM IRST and Singapore works 9:00 AM - 6:00 PM SGT (+4h 30m difference). Try scheduling during the overlapping window for maximum convenience.

What currencies are used in Tehran and Singapore?

Tehran uses IRR (﷼) while Singapore uses SGD (S$). Check current exchange rates when planning travel or business between these cities.

How do Tehran and Singapore compare in size?

Tehran has a population of approximately 9.4 million (metro: 16.8 million), while Singapore has approximately 5.5 million (metro: 5.9 million).

What are the major landmarks in Tehran and Singapore?

Tehran is known for Azadi Tower, Golestan Palace, Grand Bazaar. Singapore is famous for Marina Bay Sands, Gardens by the Bay, Merlion.

Do Tehran and Singapore have stock exchanges?

Yes. Tehran has the TSE (Tehran Stock Exchange) and Singapore has the SGX (Singapore Exchange). The +4h 30m time difference affects trading hour overlaps between these exchanges.