Offset
The time difference between Mountain Time and Tokyo is 15 hours.
Mountain Time (MDT) is behind Tokyo (JST).
MDT: UTC-6
JST: UTC+9
Mountain Time is currently observing daylight saving time; Tokyo is not.
When to schedule
Standard business hours (9 AM–5 PM, Mon–Fri) in Mountain Time and Tokyo don't overlap on the same weekday. Tokyo is 15 hours ahead of Mountain Time.
With some flexibility, there’s a workable window outside standard hours:
- 4 PM–8 PM in Mountain Time (7 AM–11 AM the next day in Tokyo) — suggest 6:00 PM Mountain Time (9:00 AM Tokyo).
This means an early start or late finish for one side, but it’s a reasonable slot for a one-off meeting.
This window may shift by an hour during daylight saving time.
Public holidays in 2026
National public holidays can affect availability — a counterpart is likely off work on their own holidays, so it's worth planning meetings and deadlines around them.
United States
- New Year's DayThu, Jan 1
- Martin Luther King, Jr. DayMon, Jan 19
- Presidents DayMon, Feb 16
- Memorial DayMon, May 25
- Juneteenth National Independence DayFri, Jun 19
- Independence DayFri, Jul 3
- Labour DayMon, Sep 7
- Columbus DayMon, Oct 12
- Veterans DayWed, Nov 11
- Thanksgiving DayThu, Nov 26
- Christmas DayFri, Dec 25
Japan
- New Year's DayThu, Jan 1
- Coming of Age DayMon, Jan 12
- Foundation DayWed, Feb 11
- The Emperor's BirthdayMon, Feb 23
- Vernal Equinox DayFri, Mar 20
- Shōwa DayWed, Apr 29
- Constitution Memorial DayWed, May 6
- Greenery DayMon, May 4
- Children's DayTue, May 5
- Marine DayMon, Jul 20
- Mountain DayTue, Aug 11
- Respect for the Aged DayMon, Sep 21
- Autumnal Equinox DayWed, Sep 23
- Sports DayMon, Oct 12
- Culture DayTue, Nov 3
- Labour Thanksgiving DayMon, Nov 23
About these zones
Mountain Time is also known as MST, or MDT. To call United States, dial +1.
Tokyo uses Japan Standard Time (JST). To call Japan, dial +81.
Tokyo is approximately 5,800 miles northwest of Mountain Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| MST | Tokyo | Day |
|---|---|---|
| 12:00 am | 3:00 pm | Same day |
| 1:00 am | 4:00 pm | Same day |
| 2:00 am | 5:00 pm | Same day |
| 3:00 am | 6:00 pm | Same day |
| 4:00 am | 7:00 pm | Same day |
| 5:00 am | 8:00 pm | Same day |
| 6:00 am | 9:00 pm | Same day |
| 7:00 am | 10:00 pm | Same day |
| 8:00 am | 11:00 pm | Same day |
| 9:00 am | 12:00 am | +1 day |
| 10:00 am | 1:00 am | +1 day |
| 11:00 am | 2:00 am | +1 day |
| 12:00 pm | 3:00 am | +1 day |
| 1:00 pm | 4:00 am | +1 day |
| 2:00 pm | 5:00 am | +1 day |
| 3:00 pm | 6:00 am | +1 day |
| 4:00 pm | 7:00 am | +1 day |
| 5:00 pm | 8:00 am | +1 day |
| 6:00 pm | 9:00 am | +1 day |
| 7:00 pm | 10:00 am | +1 day |
| 8:00 pm | 11:00 am | +1 day |
| 9:00 pm | 12:00 pm | +1 day |
| 10:00 pm | 1:00 pm | +1 day |
| 11:00 pm | 2:00 pm | +1 day |
Daylight saving time
Mountain Time observes daylight saving time; Tokyo does not. The offset between the two zones changes when Mountain Time transitions: on Sunday, November 1, 2026, clocks fall back from MDT to MST.
See the daylight saving time page for transition dates across every time zone.
Daylight today
- Sunrise
- 5:34 AM
- Sunset
- 8:25 PM
- Day length
- 14h 52m
- Sunrise
- 4:27 AM
- Sunset
- 6:54 PM
- Day length
- 14h 28m
Cities in these zones
Cities in Mountain Time
Other cities in Japan Standard Time
Browse all cities to see the current local time anywhere.
Airports in these zones
Airports in Mountain Time
- BJC
- DEN
- OGD
- SLC
Airports in Japan Standard Time
- HND
- NRT
- ITM
- KIX
- UKB
- NGO
- NKM
- CTS
- OKD
- FUK
Related conversions
Common conversions
- What is 9:00 am MST in Tokyo?
- 9:00 am MST is 12:00 am Tokyo, the next day.
- What is 12:00 pm MST in Tokyo?
- 12:00 pm MST is 3:00 am Tokyo, the next day.
- What is 12:30 pm MST in Tokyo?
- 12:30 pm MST is 3:30 am Tokyo, the next day.
- What is 2:00 pm MST in Tokyo?
- 2:00 pm MST is 5:00 am Tokyo, the next day.
- What is 5:00 pm MST in Tokyo?
- 5:00 pm MST is 8:00 am Tokyo, the next day.
- What is 11:30 pm MST in Tokyo?
- 11:30 pm MST is 2:30 pm Tokyo, the next day.