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 MDT

-9h 30m

Tehran

IRSTSOURCE

Iran · UTC+03:30

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

MDT

UTC-06:00☀ DST active

HH02

MM30

02:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Tehran

MDT

12:00 AM

2:30 PM-1

2:00 AM

4:30 PM-1

4:00 AM

6:30 PM-1

6:00 AM

8:30 PM-1

8:00 AM

10:30 PM-1

10:00 AM

12:30 AM

12:00 PM

2:30 AM

2:00 PM

4:30 AM

4:00 PM

6:30 AM

6:00 PM

8:30 AM

8:00 PM

10:30 AM

10:00 PM

12:30 PM

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

IRST and MDT on the World Map

The map below highlights the IRST (Iran Standard Time) and MDT (Mountain Daylight Time) timezone regions across the globe.

IRST Zone

→

MDT 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

MDT – Mountain Daylight Time

UTC-06:00

Mountain Daylight Time (MDT) is the daylight saving offset in the Mountain Time Zone, 6 hours behind UTC.

Countries in MDT

United States (Mountain)Canada (Alberta)

Major Cities in MDT

DenverCalgaryEdmontonSalt Lake CityBoise

Key Facts about MDT

•MDT shares the same offset as CST (UTC-06:00).
•Arizona does not switch to MDT, remaining on MST.

Daylight Saving:Yes – switches to MST

Learn more about MDT 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 →

Everything You Need to Know About Tehran and MDT Time

Tehran runs on Iran Standard Time (IRST) at UTC+03:30. MDT runs on Mountain Daylight Time (MDT) at UTC-06:00. That puts Tehran 9 hours 30 minutes behind MDT — a difference of -9h 30m at the current offsets.

In practice, when it is 9:00 AM in Tehran it is 11:30 PM in MDT on the previous day. Midnight in Tehran is 2:30 PM in MDT. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Tehran to MDT time conversion table

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

Why people convert Tehran to MDT time

Scheduling a call from Tehran to MDT: a 10:00 AM start in Tehran lands at 12:30 AM in MDT, so you can confirm the slot without doing the arithmetic yourself.
Handling a -9h 30m gap: Tehran and MDT have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in MDT is 11:30 PM in Tehran.
Keeping family and friends in sync: knowing that 8:00 PM in Tehran is 10:30 AM in MDT makes it easy to avoid calling at 3 AM.

Always state the zone abbreviation, not just the hour. "3:00 PM IRST" is unambiguous; "3 PM" across a -9h 30m gap is not.
With a -9h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week Tehran takes the early slot, the next week MDT does.

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 MDT (Mountain Daylight Time)

Mountain Daylight Time (MDT) is observed during summer months in the Mountain Time Zone, except in Arizona which stays on MST year-round. MDT aligns with Central Standard Time (CST) at UTC-06:00.

Best time to call between Tehran and MDT

With a -9h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. MDT opens at 9:00 AM MDT, which is 11:30 PM in Tehran, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Tehran and MDT have no shared working hours because of the -9h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.

Tehran is 9 hours 30 minutes behind MDT (IRST UTC+03:30 → MDT UTC-06:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

Tehran

Does not observe DST

MDT

☀ Currently in DST

Standard: UTC-07:00 · DST: UTC-06:00

Clocks fall back on Sun, Nov 1, 2026

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 MDT?

Tehran (IRST, UTC+03:30) is 9 hours 30 minutes behind MDT (MDT, UTC-06:00). The gap is currently -9h 30m.

How do I convert Tehran time to MDT time?

Add -9h 30m to Tehran local time. For example, 9:00 AM in Tehran is 11:30 PM in MDT (previous day).

What time is it in MDT right now?

MDT uses MDT at UTC-06:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -9h 30m offset from Tehran.

What is the best time to call MDT from Tehran?

There is no shared working-hours window because of the -9h 30m gap. The closest option is 1:00 PM in Tehran, which is 3:30 AM in MDT.

Which is behind, Tehran or MDT?

Tehran is 9 hours 30 minutes behind MDT. When it is 12:00 PM in Tehran it is 2:30 AM in MDT.

Do Tehran and MDT use different time zones?

Tehran (Iran) uses IRST at UTC+03:30, while MDT uses MDT at UTC-06:00. The IANA identifiers are Asia/Tehran and America/Denver.

Does daylight saving time affect the Tehran–MDT difference?

Neither zone observes daylight saving time, so the -9h 30m offset between Tehran and MDT 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 MDT?

Not normally. The -9h 30m gap only pushes the date over the previous day.

What is the time difference between Tehran and MDT?

MDT is -9h 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.