World Timezones

MST to JST Converter

Compare JST to MST instead

Search above to add a time zone or city

Offset

15 hours

Mountain Time (MST) is currently behind Japan Standard Time (JST).

MST: UTC-6

JST: UTC+9

Mountain Time is currently observing daylight saving time; Japan Standard Time is not.

When to schedule

Standard business hours (9 AM–5 PM, Mon–Fri) in Mountain Time and Japan Standard Time don't overlap on the same weekday. Japan Standard Time is 15 hours ahead of Mountain Time.

Realistic options: hand off asynchronously, or stretch one side by an hour to catch the other team at the start or end of their day.

This window may shift by an hour during daylight saving time.

About these zones

Mountain Time is also known as MST, or MDT.

Japan Standard Time is also known as JST.

Mountain Time and Japan Standard Time are approximately 5,800 miles apart.

Quick reference

Full 24-hour conversion table.

MSTJSTDay
12:00 am3:00 pm-1 day
1:00 am4:00 pm-1 day
2:00 am5:00 pm-1 day
3:00 am6:00 pm-1 day
4:00 am7:00 pm-1 day
5:00 am8:00 pm-1 day
6:00 am9:00 pm-1 day
7:00 am10:00 pm-1 day
8:00 am11:00 pm-1 day
9:00 am12:00 amSame day
10:00 am1:00 amSame day
11:00 am2:00 amSame day
12:00 pm3:00 amSame day
1:00 pm4:00 amSame day
2:00 pm5:00 amSame day
3:00 pm6:00 amSame day
4:00 pm7:00 amSame day
5:00 pm8:00 amSame day
6:00 pm9:00 amSame day
7:00 pm10:00 amSame day
8:00 pm11:00 amSame day
9:00 pm12:00 pmSame day
10:00 pm1:00 pmSame day
11:00 pm2:00 pmSame day

Daylight saving time

Mountain Time observes daylight saving time; Japan Standard Time 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.

Daylight today

Mountain Time
Sunrise
5:37 AM
Sunset
8:19 PM
Day length
14h 41m
Japan Standard Time
Sunrise
4:30 AM
Sunset
6:49 PM
Day length
14h 19m

Cities in these zones

Cities in Mountain Time

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

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