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).

São Paulo to Tehran

+6h 30m

São Paulo

BRTSOURCE

Brazil · UTC-03:00

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Tehran

IRST

Iran · UTC+03:30

HH06

MM30

18:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

São Paulo

Tehran

12:00 AM

6:30 AM

2:00 AM

8:30 AM

4:00 AM

10:30 AM

6:00 AM

12:30 PM

8:00 AM

2:30 PM

10:00 AM

4:30 PM

12:00 PM

6:30 PM

2:00 PM

8:30 PM

4:00 PM

10:30 PM

6:00 PM

12:30 AM+1

8:00 PM

2:30 AM+1

10:00 PM

4:30 AM+1

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

BRT and IRST on the World Map

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

BRT Zone

→

IRST Zone

Explore all world timezones interactively →

BRT – Brasilia Time

UTC-03:00

Brasilia Time (BRT) is the time zone for eastern Brazil, 3 hours behind UTC.

Countries in BRT

Brazil (eastern)

Major Cities in BRT

São PauloRio de JaneiroBrasíliaBelo HorizonteSalvadorFortalezaRecifeCuritiba

Key Facts about BRT

•Brazil abolished daylight saving time in 2019.
•São Paulo is the largest city in the Southern Hemisphere.
•BRT is 2 hours ahead of EST.
•Brazil spans four different time zones.
•The B3 stock exchange in São Paulo operates on BRT.

Daylight Saving:No – UTC-03:00 year-round

Learn more about BRT 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 São Paulo

Wikipedia

São Paulo operates on Brasília Time (BRT), UTC-3. As South America's largest financial center, São Paulo's B3 exchange is the Americas' second-largest.

Population:12.4 million

Metro:22.4 million

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

Currency:BRL (R$)

Stock Exchange:B3 (Brasil Bolsa Balcão)

Key Landmarks

Paulista AvenueIbirapuera ParkSão Paulo CathedralMASPPinacoteca

Did You Know?

The city has more helicopters than any other city in the world due to traffic congestion.

Learn more about BRT 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 →

Everything You Need to Know About São Paulo and Tehran Time

São Paulo runs on Brasilia Standard Time (BRT) at UTC-03:00. Tehran runs on Iran Standard Time (IRST) at UTC+03:30. That puts São Paulo 6 hours 30 minutes ahead of Tehran — a difference of +6h 30m at the current offsets.

In practice, when it is 9:00 AM in São Paulo it is 3:30 PM in Tehran. Midnight in São Paulo is 6:30 AM in Tehran. Neither zone observes daylight saving time, so the offset between them stays constant all year.

São Paulo to Tehran time conversion table

São Paulo (BRT)	Tehran (IRST)	Day
12:00 AM	6:30 AM	same day
6:00 AM	12:30 PM	same day
7:00 AM	1:30 PM	same day
8:00 AM	2:30 PM	same day
9:00 AM	3:30 PM	same day
12:00 PM	6:30 PM	same day
3:00 PM	9:30 PM	same day
5:00 PM	11:30 PM	same day
6:00 PM	12:30 AM	next day
9:00 PM	3:30 AM	next day

Why people convert São Paulo to Tehran time

Scheduling a call from São Paulo to Tehran: a 10:00 AM start in São Paulo lands at 4:30 PM in Tehran, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both São Paulo and Tehran are inside the 9-to-5 working day between 9:00 AM and 10:30 AM BRT time (3:30 PM–5:00 PM IRST). That is roughly 1 hours 30 minutes of usable overlap.
Watching a live event or market open: São Paulo viewers need 3:30 PM in Tehran to catch a 9:00 AM start there, and 5:30 PM if the event is anchored to São Paulo.

Always state the zone abbreviation, not just the hour. "3:00 PM BRT" is unambiguous; "3 PM" across a +6h 30m gap is not.
Block 9:00 AM–10:30 AM BRT as the recurring meeting window if you work primarily from São Paulo and need Tehran colleagues present.

About BRT (Brasilia Time)

Brasilia Time (BRT) is the standard time in the most populous regions of Brazil, including São Paulo, Rio de Janeiro, and the capital Brasília. Brazil abolished daylight saving time in 2019, so BRT is now observed year-round in these regions. Brazil spans four time zones in total.

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 São Paulo and Tehran

Both São Paulo and Tehran sit inside the 9 AM – 5 PM working day between 9:00 AM–10:30 AM BRT, which is 3:30 PM–5:00 PM IRST. That gives roughly 1 hours and 30 minutes of shared time — the safest window for a live call or meeting.

Business hours overlap

São Paulo and Tehran overlap for only 90 minutes (9:00 AM–10:30 AM BRT), so meetings have to be booked precisely.

São Paulo is 6 hours 30 minutes ahead of Tehran (BRT UTC-03:00 → IRST UTC+03:30). The shared working window is 9:00 AM–10:30 AM BRT. 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 São Paulo and Tehran?

São Paulo (BRT, UTC-03:00) is 6 hours 30 minutes ahead of Tehran (IRST, UTC+03:30). The gap is currently +6h 30m.

How do I convert São Paulo time to Tehran time?

Add +6h 30m to São Paulo local time. For example, 9:00 AM in São Paulo is 3:30 PM 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 +6h 30m offset from São Paulo.

What is the best time to call Tehran from São Paulo?

Call between 9:00 AM and 10:30 AM BRT — that maps to 3:30 PM–5:00 PM IRST and keeps both parties inside the working day.

Which is ahead, São Paulo or Tehran?

São Paulo is 6 hours 30 minutes ahead of Tehran. When it is 12:00 PM in São Paulo it is 6:30 PM in Tehran.

Do São Paulo and Tehran use different time zones?

São Paulo (Brazil) uses BRT at UTC-03:00, while Tehran (Iran) uses IRST at UTC+03:30. The IANA identifiers are America/Sao_Paulo and Asia/Tehran.

Does daylight saving time affect the São Paulo–Tehran difference?

Neither zone observes daylight saving time, so the +6h 30m offset between São Paulo and Tehran is fixed all year.

Which other cities share São Paulo's time zone?

BRT also covers São Paulo, Rio de Janeiro, Brasília, Belo Horizonte, Salvador, Fortaleza, Recife, Curitiba.

Which countries use BRT, São Paulo's zone?

BRT is used in Brazil (eastern).

Is there a day difference between São Paulo and Tehran?

Not normally. The +6h 30m gap only pushes the date over for late-evening times.

What is the time difference between São Paulo and Tehran?

Tehran is +6h 30m from São Paulo.

What timezone is São Paulo in?

São Paulo operates on Brasília Time (BRT), UTC-3. As South America's largest financial center, São Paulo's B3 exchange is the Americas' second-largest.

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 São Paulo?

Standard business hours in São Paulo are 9:00 AM - 6:00 PM BRT.

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 São Paulo and Tehran?

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

What currencies are used in São Paulo and Tehran?

São Paulo uses BRL (R$) while Tehran uses IRR (﷼). Check current exchange rates when planning travel or business between these cities.

How do São Paulo and Tehran compare in size?

São Paulo has a population of approximately 12.4 million (metro: 22.4 million), while Tehran has approximately 9.4 million (metro: 16.8 million).

What are the major landmarks in São Paulo and Tehran?

São Paulo is known for Paulista Avenue, Ibirapuera Park, São Paulo Cathedral. Tehran is famous for Azadi Tower, Golestan Palace, Grand Bazaar.

Do São Paulo and Tehran have stock exchanges?

Yes. São Paulo has the B3 (Brasil Bolsa Balcão) and Tehran has the TSE (Tehran Stock Exchange). The +6h 30m time difference affects trading hour overlaps between these exchanges.