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.

Singapore to Tehran

-4h 30m

Singapore

SGTSOURCE

Singapore · UTC+08:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Tehran

IRST

Iran · UTC+03:30

HH07

MM30

07:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Singapore

Tehran

12:00 AM

7:30 PM-1

2:00 AM

9:30 PM-1

4:00 AM

11:30 PM-1

6:00 AM

1:30 AM

8:00 AM

3:30 AM

10:00 AM

5:30 AM

12:00 PM

7:30 AM

2:00 PM

9:30 AM

4:00 PM

11:30 AM

6:00 PM

1:30 PM

8:00 PM

3:30 PM

10:00 PM

5:30 PM

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

SGT and IRST on the World Map

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

SGT Zone

→

IRST Zone

Explore all world timezones interactively →

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

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

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 →

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: Singapore to Tehran

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

In practice, when it is 9:00 AM in Singapore it is 4:30 AM in Tehran. Midnight in Singapore is 7:30 PM in Tehran. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Singapore to Tehran time conversion table

Singapore (SGT)	Tehran (IRST)	Day
12:00 AM	7:30 PM	previous day
6:00 AM	1:30 AM	same day
7:00 AM	2:30 AM	same day
8:00 AM	3:30 AM	same day
9:00 AM	4:30 AM	same day
12:00 PM	7:30 AM	same day
3:00 PM	10:30 AM	same day
5:00 PM	12:30 PM	same day
6:00 PM	1:30 PM	same day
9:00 PM	4:30 PM	same day

Why people convert Singapore to Tehran time

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

Always state the zone abbreviation, not just the hour. "3:00 PM SGT" is unambiguous; "3 PM" across a -4h 30m gap is not.
Block 1:30 PM–5:00 PM SGT as the recurring meeting window if you work primarily from Singapore and need Tehran colleagues present.

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.

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 Singapore and Tehran

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

Business hours overlap

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

Singapore is 4 hours 30 minutes behind Tehran (SGT UTC+08:00 → IRST UTC+03:30). The shared working window is 1:30 PM–5:00 PM SGT. 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 Singapore and Tehran?

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

How do I convert Singapore time to Tehran time?

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

What time is it in Tehran right now?

Tehran 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 -4h 30m offset from Singapore.

What is the best time to call Tehran from Singapore?

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

Which is behind, Singapore or Tehran?

Singapore is 4 hours 30 minutes behind Tehran. When it is 12:00 PM in Singapore it is 7:30 AM in Tehran.

Do Singapore and Tehran use different time zones?

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

Does daylight saving time affect the Singapore–Tehran difference?

Neither zone observes daylight saving time, so the -4h 30m offset between Singapore and Tehran is fixed all year.

Which other cities share Singapore's time zone?

SGT also covers Singapore.

Which countries use SGT, Singapore's zone?

SGT is used in Singapore.

Is there a day difference between Singapore and Tehran?

Not normally. The -4h 30m gap only pushes the date over the previous day.

What is the time difference between Singapore and Tehran?

Tehran is -4h 30m from Singapore.

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 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 are the business hours in Singapore?

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

What are the business hours in Tehran?

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

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

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

What currencies are used in Singapore and Tehran?

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

How do Singapore and Tehran compare in size?

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

What are the major landmarks in Singapore and Tehran?

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

Do Singapore and Tehran have stock exchanges?

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