MST to KST
+16hMST
MSTSOURCEKST
KSTGreen rows indicate typical business hours (9 AM - 5 PM)
MST and KST on the World Map
The map below highlights the MST (Mountain Standard Time) and KST (Korea Standard Time) timezone regions across the globe.
MST – Mountain Standard Time
UTC-07:00Mountain Standard Time (MST) is the time zone for the Mountain region of North America, 7 hours behind UTC.
- •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.
KST – Korea Standard Time
UTC+09:00Korea Standard Time (KST) is the time zone for South Korea, 9 hours ahead of UTC.
- •South Korea does not observe daylight saving time.
- •Seoul is home to Samsung, LG, and Hyundai headquarters.
- •KST is the same offset as JST (UTC+09:00).
Understanding the +16h Gap: MST vs KST
MST runs on Mountain Standard Time (MST) at UTC-07:00. KST runs on Korea Standard Time (KST) at UTC+09:00. That puts MST 16 hours ahead of KST — a difference of +16h at the current offsets.
In practice, when it is 9:00 AM in MST it is 1:00 AM in KST on the next day. Midnight in MST is 4:00 PM in KST. Neither zone observes daylight saving time, so the offset between them stays constant all year.
MST to KST time conversion table
| MST (MST) | KST (KST) | Day |
|---|---|---|
| 12:00 AM | 4:00 PM | same day |
| 6:00 AM | 10:00 PM | same day |
| 7:00 AM | 11:00 PM | same day |
| 8:00 AM | 12:00 AM | next day |
| 9:00 AM | 1:00 AM | next day |
| 12:00 PM | 4:00 AM | next day |
| 3:00 PM | 7:00 AM | next day |
| 5:00 PM | 9:00 AM | next day |
| 6:00 PM | 10:00 AM | next day |
| 9:00 PM | 1:00 PM | next day |
Why people convert MST to KST time
- Scheduling a call from MST to KST: a 10:00 AM start in MST lands at 2:00 AM in KST the next day, so you can confirm the slot without doing the arithmetic yourself.
- Handling a +16h gap: MST and KST 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 KST is 1:00 AM in MST.
- Coordinating a MST-based team with KST 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 MST" is unambiguous; "3 PM" across a +16h gap is not.
- With a +16h gap there is no shared 9-to-5 window, so alternate the early start: one week MST takes the early slot, the next week KST does.
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 KST (Korea Standard Time)
Korea Standard Time (KST) is the time zone used in South Korea. It shares the same UTC offset as Japan Standard Time but is a distinct time zone. South Korea does not observe daylight saving time. Seoul, the capital, is a major global tech and business hub.
Best time to call between MST and KST
With a +16h offset there is no overlap inside a normal 9 AM – 5 PM day. KST opens at 9:00 AM KST, which is 1:00 AM in MST, so real-time calls need an early-morning or late-evening slot on one side.
Business hours overlap
MST and KST have no shared working hours because of the +16h gap. Teams need to alternate early starts or rely on asynchronous handovers.
MST is 16 hours ahead of KST (MST UTC-07:00 → KST UTC+09:00). 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
MST
☀ Currently in DST
Standard: UTC-07:00 · DST: UTC-06:00
Clocks fall back on Sun, Nov 1, 2026
KST
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:
Frequently Asked Questions
What is the time difference between MST and KST?
MST (MST, UTC-07:00) is 16 hours ahead of KST (KST, UTC+09:00). The gap is currently +16h.
How do I convert MST time to KST time?
Add +16h to MST local time. For example, 9:00 AM in MST is 1:00 AM in KST (next day).
What time is it in KST right now?
KST uses KST at UTC+09:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +16h offset from MST.
What is the best time to call KST from MST?
There is no shared working-hours window because of the +16h gap. The closest option is 1:00 PM in MST, which is 5:00 AM in KST.
Which is ahead, MST or KST?
MST is 16 hours ahead of KST. When it is 12:00 PM in MST it is 4:00 AM in KST.
Does daylight saving time affect the MST–KST difference?
Neither zone observes daylight saving time, so the +16h offset between MST and KST is fixed all year.
Which other cities share MST's time zone?
MST also covers Denver, Phoenix, Salt Lake City, Calgary, Edmonton, Albuquerque, El Paso, Tucson and 2 more.
Which countries use MST, MST's zone?
MST is used in United States (Mountain), Canada (Alberta), Mexico (Chihuahua, Sonora).
Is there a day difference between MST and KST?
Sometimes. The +16h gap is large enough that 8:00 PM or later in MST already falls on the next day in KST.
What is the time difference between MST and KST?
KST is +16h from MST.
What timezone is MST in?
MST operates on its local timezone.
What timezone is KST in?
KST operates on its local timezone.
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.
Which cities are in the KST timezone?
Major cities in the KST timezone include Seoul, Busan, Incheon, Daegu, Daejeon, Pyongyang.
What is the UTC offset for KST?
Korea Standard Time (KST) is at UTC+09:00.
What should I know about the KST timezone?
South Korea does not observe daylight saving time. Seoul is home to Samsung, LG, and Hyundai headquarters.
When is it midnight in MST, what time is it in KST?
When it is 12:00 AM (midnight) in MST (MST), it is +16h later in KST (KST).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More MST time conversions
- mst to denver
- mst to mdt
- mst to new york
- mst to london
- mst to dubai
- mst to tokyo
- mst to singapore
- mst to sydney
- mst to los angeles
- mst to paris
- mst to delhi
- mst to mumbai
- mst to berlin
- mst to hong kong
- mst to toronto
- mst to kathmandu
- new york to mst
- london to mst
- dubai to mst
- tokyo to mst
- singapore to mst
- sydney to mst
- los angeles to mst
- paris to mst
- delhi to mst
- mumbai to mst
- berlin to mst
- hong kong to mst
- toronto to mst
- kathmandu to mst
See every conversion from MST →·See every conversion from KST →