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).

Denver to HST

-4h

Denver

MDTSOURCE

USA · UTC-06:00☀ DST active

HH12

MM00

12:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

HST

UTC-10:00

HH08

MM00

08:00 (24-hr)

12 AM6 AM12 PM6 PM12 AM

Quick Reference

Time Conversion Table

Denver

HST

12:00 AM

8:00 PM-1

2:00 AM

10:00 PM-1

4:00 AM

12:00 AM

6:00 AM

2:00 AM

8:00 AM

4:00 AM

10:00 AM

6:00 AM

12:00 PM

8:00 AM

2:00 PM

10:00 AM

4:00 PM

12:00 PM

6:00 PM

2:00 PM

8:00 PM

4:00 PM

10:00 PM

6:00 PM

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

MDT and HST on the World Map

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

MDT Zone

→

HST Zone

Explore all world timezones interactively →

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

HST – Hawaii Standard Time

UTC-10:00

Hawaii Standard Time (HST) is the time zone for the Hawaiian Islands, 10 hours behind UTC.

Countries in HST

United States (Hawaii)

Major Cities in HST

HonoluluHiloKailuaPearl CityKapolei

Key Facts about HST

•Hawaii does not observe daylight saving time.
•HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.
•Hawaii is one of only two US states that don't observe DST (the other is Arizona).

Daylight Saving:No – UTC-10:00 year-round

Learn more about HST on Wikipedia

About Denver

Wikipedia

Denver operates on Mountain Time (MST/MDT), 2 hours behind New York. As a tech and aerospace hub, Denver bridges West Coast and Central US business hours.

Population:715,000

Metro:2.9 million

Business Hours:8:00 AM - 5:00 PM MST

Currency:USD ($)

Key Landmarks

Red Rocks AmphitheatreDenver Art MuseumUnion Station16th Street MallColorado State Capitol

Did You Know?

Denver International Airport is the largest airport in North America by land area.

Learn more about MDT timezone →

Everything You Need to Know About Denver and HST Time

Denver runs on Mountain Daylight Time (MDT) at UTC-06:00, currently observing daylight saving time. HST runs on Hawaii Standard Time (HST) at UTC-10:00. That puts Denver 4 hours behind HST — a difference of -4h at the current offsets.

In practice, when it is 9:00 AM in Denver it is 5:00 AM in HST. Midnight in Denver is 8:00 PM in HST.Denver observes daylight saving time while HST does not, so the gap narrows or widens by an hour part of the year.

Denver to HST time conversion table

Denver (MDT)	HST (HST)	Day
12:00 AM	8:00 PM	previous day
6:00 AM	2:00 AM	same day
7:00 AM	3:00 AM	same day
8:00 AM	4:00 AM	same day
9:00 AM	5:00 AM	same day
12:00 PM	8:00 AM	same day
3:00 PM	11:00 AM	same day
5:00 PM	1:00 PM	same day
6:00 PM	2:00 PM	same day
9:00 PM	5:00 PM	same day

Why people convert Denver to HST time

Scheduling a call from Denver to HST: a 10:00 AM start in Denver lands at 6:00 AM in HST, so you can confirm the slot without doing the arithmetic yourself.
Finding shared working hours: both Denver and HST are inside the 9-to-5 working day between 1:00 PM and 5:00 PM MDT time (9:00 AM–1:00 PM HST). That is roughly 4 hours of usable overlap.
Keeping family and friends in sync: knowing that 8:00 PM in Denver is 4:00 PM in HST makes it easy to avoid calling at 3 AM.

Always state the zone abbreviation, not just the hour. "3:00 PM MDT" is unambiguous; "3 PM" across a -4h gap is not.
Block 1:00 PM–5:00 PM MDT as the recurring meeting window if you work primarily from Denver and need HST colleagues present.
Denver: Clocks fall back on Sun, Nov 1, 2026. Re-check this page after that date because the offset changes and so does the -4h gap.

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).

About HST (Hawaii Standard Time)

Hawaii Standard Time (HST) is used in the state of Hawaii and does not observe daylight saving time. This makes HST one of the most consistent time zones in the US. The Hawaiian Islands are among the last places on Earth to see a new calendar day.

Best time to call between Denver and HST

Both Denver and HST sit inside the 9 AM – 5 PM working day between 1:00 PM–5:00 PM MDT, which is 9:00 AM–1:00 PM HST. That gives roughly 4 hours of shared time — the safest window for a live call or meeting.

Business hours overlap

Denver and HST overlap for about 4 hours during the working day — enough for meetings if you avoid the edges of the window.

Denver is 4 hours behind HST (MDT UTC-06:00 → HST UTC-10:00). The shared working window is 1:00 PM–5:00 PM MDT. Remember to re-check around daylight-saving transitions.

🕐 Daylight Saving Time Info

Denver

☀ Currently in DST

Standard: UTC-07:00 · DST: UTC-06:00

Clocks fall back on Sun, Nov 1, 2026

HST

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 Denver and HST?

Denver (MDT, UTC-06:00) is 4 hours behind HST (HST, UTC-10:00). The gap is currently -4h.

How do I convert Denver time to HST time?

Add -4h to Denver local time. For example, 9:00 AM in Denver is 5:00 AM in HST.

What time is it in HST right now?

HST uses HST at UTC-10:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -4h offset from Denver.

What is the best time to call HST from Denver?

Call between 1:00 PM and 5:00 PM MDT — that maps to 9:00 AM–1:00 PM HST and keeps both parties inside the working day.

Which is behind, Denver or HST?

Denver is 4 hours behind HST. When it is 12:00 PM in Denver it is 8:00 AM in HST.

Do Denver and HST use different time zones?

Denver (USA) uses MDT at UTC-06:00, while HST uses HST at UTC-10:00. The IANA identifiers are America/Denver and Pacific/Honolulu.

Does daylight saving time affect the Denver–HST difference?

Yes at the moment: Denver is on daylight saving time and HST is not, so the -4h gap shifts by an hour when exactly one of them changes clocks.

Which other cities share Denver's time zone?

MDT also covers Denver, Phoenix, Salt Lake City, Calgary, Edmonton, Albuquerque, El Paso, Tucson and 2 more.

Which countries use MDT, Denver's zone?

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

Is there a day difference between Denver and HST?

Not normally. The -4h gap only pushes the date over the previous day.

What is the time difference between Denver and HST?

HST is -4h from Denver.

What timezone is Denver in?

Denver operates on Mountain Time (MST/MDT), 2 hours behind New York. As a tech and aerospace hub, Denver bridges West Coast and Central US business hours.

What timezone is HST in?

HST operates on its local timezone.

What are the business hours in Denver?

Standard business hours in Denver are 8:00 AM - 5:00 PM MST.

Which countries use MST (Mountain Standard Time)?

MST is used in United States (Mountain), Canada (Alberta), Mexico (Chihuahua, Sonora).

Does MST observe daylight saving time?

Yes, MST switches to MDT during summer months.

What are some interesting 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.