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 BRT

-6h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

BRT

UTC-03:00

HH05

MM30

05:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

BRT

12:00 AM

5:30 PM-1

2:00 AM

7:30 PM-1

4:00 AM

9:30 PM-1

6:00 AM

11:30 PM-1

8:00 AM

1:30 AM

10:00 AM

3:30 AM

12:00 PM

5:30 AM

2:00 PM

7:30 AM

4:00 PM

9:30 AM

6:00 PM

11:30 AM

8:00 PM

1:30 PM

10:00 PM

3:30 PM

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

IRST and BRT on the World Map

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

IRST Zone

→

BRT 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

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

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 →

Tehran vs BRT: Offsets, DST and Best Call Times

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

In practice, when it is 9:00 AM in Tehran it is 2:30 AM in BRT. Midnight in Tehran is 5:30 PM in BRT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Tehran to BRT time conversion table

Tehran (IRST)	BRT (BRT)	Day
12:00 AM	5:30 PM	previous day
6:00 AM	11:30 PM	previous day
7:00 AM	12:30 AM	same day
8:00 AM	1:30 AM	same day
9:00 AM	2:30 AM	same day
12:00 PM	5:30 AM	same day
3:00 PM	8:30 AM	same day
5:00 PM	10:30 AM	same day
6:00 PM	11:30 AM	same day
9:00 PM	2:30 PM	same day

Why people convert Tehran to BRT time

Scheduling a call from Tehran to BRT: a 10:00 AM start in Tehran lands at 3:30 AM in BRT, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both Tehran and BRT are inside the 9-to-5 working day between 3:30 PM and 5:00 PM IRST time (9:00 AM–10:30 AM BRT). That is roughly 1 hours 30 minutes of usable overlap.
Coordinating a Tehran-based team with BRT 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 -6h 30m gap is not.
Block 3:30 PM–5:00 PM IRST as the recurring meeting window if you work primarily from Tehran and need BRT 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 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.

Best time to call between Tehran and BRT

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

Business hours overlap

Tehran and BRT overlap for only 90 minutes (3:30 PM–5:00 PM IRST), so meetings have to be booked precisely.

Tehran is 6 hours 30 minutes behind BRT (IRST UTC+03:30 → BRT UTC-03:00). The shared working window is 3:30 PM–5:00 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 BRT?

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

How do I convert Tehran time to BRT time?

Add -6h 30m to Tehran local time. For example, 9:00 AM in Tehran is 2:30 AM in BRT.

What time is it in BRT right now?

BRT uses BRT at UTC-03:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -6h 30m offset from Tehran.

What is the best time to call BRT from Tehran?

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

Which is behind, Tehran or BRT?

Tehran is 6 hours 30 minutes behind BRT. When it is 12:00 PM in Tehran it is 5:30 AM in BRT.

Do Tehran and BRT use different time zones?

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

Does daylight saving time affect the Tehran–BRT difference?

Neither zone observes daylight saving time, so the -6h 30m offset between Tehran and BRT 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 BRT?

Not normally. The -6h 30m gap only pushes the date over the previous day.

What is the time difference between Tehran and BRT?

BRT is -6h 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.