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.

MDT to Tehran

+9h 30m

MDT

MDTSOURCE

UTC-06:00☀ DST active

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Tehran

IRST

Iran · UTC+03:30

HH09

MM30

21:30 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

MDT

Tehran

12:00 AM

9:30 AM

2:00 AM

11:30 AM

4:00 AM

1:30 PM

6:00 AM

3:30 PM

8:00 AM

5:30 PM

10:00 AM

7:30 PM

12:00 PM

9:30 PM

2:00 PM

11:30 PM

4:00 PM

1:30 AM+1

6:00 PM

3:30 AM+1

8:00 PM

5:30 AM+1

10:00 PM

7:30 AM+1

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

MDT and IRST on the World Map

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

MDT Zone

→

IRST Zone

Explore all world timezones interactively →

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

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 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 MDT and Tehran Time

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

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

MDT to Tehran time conversion table

MDT (MDT)	Tehran (IRST)	Day
12:00 AM	9:30 AM	same day
6:00 AM	3:30 PM	same day
7:00 AM	4:30 PM	same day
8:00 AM	5:30 PM	same day
9:00 AM	6:30 PM	same day
12:00 PM	9:30 PM	same day
3:00 PM	12:30 AM	next day
5:00 PM	2:30 AM	next day
6:00 PM	3:30 AM	next day
9:00 PM	6:30 AM	next day

Why people convert MDT to Tehran time

Scheduling a call from MDT to Tehran: a 10:00 AM start in MDT lands at 7:30 PM in Tehran, so you can confirm the slot without doing the arithmetic yourself.
Handling a +9h 30m gap: MDT and Tehran 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 Tehran is 6:30 PM in MDT.
Watching a live event or market open: MDT viewers need 6:30 PM in Tehran to catch a 9:00 AM start there, and 2:30 PM if the event is anchored to MDT.

Always state the zone abbreviation, not just the hour. "3:00 PM MDT" 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 MDT takes the early slot, the next week Tehran does.

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.

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 MDT and Tehran

With a +9h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. Tehran opens at 9:00 AM IRST, which is 6:30 PM in MDT, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

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

MDT is 9 hours 30 minutes ahead of Tehran (MDT UTC-06:00 → IRST UTC+03:30). 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

MDT

☀ Currently in DST

Standard: UTC-07:00 · DST: UTC-06:00

Clocks fall back on Sun, Nov 1, 2026

Tehran

Does not observe DST

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 MDT and Tehran?

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

How do I convert MDT time to Tehran time?

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

What is the best time to call Tehran from MDT?

There is no shared working-hours window because of the +9h 30m gap. The closest option is 1:00 PM in MDT, which is 10:30 PM in Tehran.

Which is ahead, MDT or Tehran?

MDT is 9 hours 30 minutes ahead of Tehran. When it is 12:00 PM in MDT it is 9:30 PM in Tehran.

Do MDT and Tehran use different time zones?

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

Does daylight saving time affect the MDT–Tehran difference?

Neither zone observes daylight saving time, so the +9h 30m offset between MDT and Tehran is fixed all year.

Which other cities share MDT's time zone?

MDT also covers Denver, Calgary, Edmonton, Salt Lake City, Boise.

Which countries use MDT, MDT's zone?

MDT is used in United States (Mountain), Canada (Alberta).

Is there a day difference between MDT and Tehran?

Not normally. The +9h 30m gap only pushes the date over for late-evening times.

What is the time difference between MDT and Tehran?

Tehran is +9h 30m from MDT.

What timezone is MDT in?

MDT operates on its local timezone.

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.