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).

MDT to MST

-1h

MDT

MDTSOURCE

UTC-06:00☀ DST active

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

MST

UTC-06:00☀ DST active

HH11

MM00

11:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

MDT

MST

12:00 AM

2:00 AM

4:00 AM

6:00 AM

8:00 AM

10:00 AM

12:00 PM

2:00 PM

4:00 PM

6:00 PM

8:00 PM

10:00 PM

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

MDT and MST on the World Map

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

MDT Zone

→

MST 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

MST – Mountain Standard Time

UTC-07:00

Mountain Standard Time (MST) is the time zone for the Mountain region of North America, 7 hours behind UTC.

Countries in MST

United States (Mountain)Canada (Alberta)Mexico (Chihuahua, Sonora)

Major Cities in MST

DenverPhoenixSalt Lake CityCalgaryEdmontonAlbuquerqueEl PasoTucsonBoiseCiudad Juárez

Key Facts about MST

•Arizona does not observe daylight saving time, staying on MST year-round.
•The Navajo Nation in Arizona does observe DST, unlike the rest of the state.
•Denver, the 'Mile High City', is the largest city fully in MST.
•MST covers 6 US states entirely and parts of several others.

Daylight Saving:Yes – switches to MDT

Learn more about MST on Wikipedia

Comparing Time Zones: MDT and MST

MDT runs on Mountain Daylight Time (MDT) at UTC-06:00. MST runs on Mountain Standard Time (MST) at UTC-07:00. That puts MDT 1 hour behind MST — a difference of -1h at the current offsets.

In practice, when it is 9:00 AM in MDT it is 8:00 AM in MST. Midnight in MDT is 11:00 PM in MST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

MDT to MST time conversion table

MDT (MDT)	MST (MST)	Day
12:00 AM	11:00 PM	previous day
6:00 AM	5:00 AM	same day
7:00 AM	6:00 AM	same day
8:00 AM	7:00 AM	same day
9:00 AM	8:00 AM	same day
12:00 PM	11:00 AM	same day
3:00 PM	2:00 PM	same day
5:00 PM	4:00 PM	same day
6:00 PM	5:00 PM	same day
9:00 PM	8:00 PM	same day

Why people convert MDT to MST time

Scheduling a call from MDT to MST: a 10:00 AM start in MDT lands at 9:00 AM in MST, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both MDT and MST are inside the 9-to-5 working day between 10:00 AM and 5:00 PM MDT time (9:00 AM–4:00 PM MST). That is roughly 7 hours of usable overlap.
Booking travel or deliveries: tracking MST local time against MDT keeps pickup windows and arrival estimates honest across the -1h offset.

Always state the zone abbreviation, not just the hour. "3:00 PM MDT" is unambiguous; "3 PM" across a -1h gap is not.
Block 10:00 AM–5:00 PM MDT as the recurring meeting window if you work primarily from MDT and need MST colleagues present.

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 MST (Mountain Standard Time)

Mountain Standard Time (MST) covers the Rocky Mountain region of the United States and Canada. Arizona is notable for not observing daylight saving time, staying on MST year-round (except the Navajo Nation). The time zone includes major cities like Denver, Phoenix, Calgary, and Salt Lake City. During summer, most areas switch to Mountain Daylight Time (MDT, UTC-06:00).

Best time to call between MDT and MST

Both MDT and MST sit inside the 9 AM – 5 PM working day between 10:00 AM–5:00 PM MDT, which is 9:00 AM–4:00 PM MST. That gives roughly 7 hours of shared time — the safest window for a live call or meeting.

Business hours overlap

MDT and MST share 7 hours of working-hours overlap (10:00 AM–5:00 PM MDT), so scheduling a live meeting is straightforward.

MDT is 1 hour behind MST (MDT UTC-06:00 → MST UTC-07:00). The shared working window is 10:00 AM–5:00 PM MDT. 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

MST

☀ 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 MDT and MST?

MDT (MDT, UTC-06:00) is 1 hour behind MST (MST, UTC-07:00). The gap is currently -1h.

How do I convert MDT time to MST time?

Add -1h to MDT local time. For example, 9:00 AM in MDT is 8:00 AM in MST.

What time is it in MST right now?

MST uses MST at UTC-07:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -1h offset from MDT.

What is the best time to call MST from MDT?

Call between 10:00 AM and 5:00 PM MDT — that maps to 9:00 AM–4:00 PM MST and keeps both parties inside the working day.

Which is behind, MDT or MST?

MDT is 1 hour behind MST. When it is 12:00 PM in MDT it is 11:00 AM in MST.

Does daylight saving time affect the MDT–MST difference?

Neither zone observes daylight saving time, so the -1h offset between MDT and MST 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 MST?

Not normally. The -1h gap only pushes the date over the previous day.

What is the time difference between MDT and MST?

MST is -1h from MDT.

What timezone is MDT in?

MDT operates on its local timezone.

What timezone is MST in?

MST operates on its local timezone.

Which countries use MDT (Mountain Daylight Time)?

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

Does MDT observe daylight saving time?

Yes, MDT switches to MST during summer months.

What are some interesting facts about MDT?

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

Which cities are in the MST timezone?

Major cities in the MST timezone include Denver, Phoenix, Salt Lake City, Calgary, Edmonton, Albuquerque, El Paso, Tucson.

What is the UTC offset for MST?

Mountain Standard Time (MST) is at UTC-07:00. During daylight saving time, it shifts to MDT.

What should I know about the MST timezone?

Arizona does not observe daylight saving time, staying on MST year-round. The Navajo Nation in Arizona does observe DST, unlike the rest of the state.