What is the time difference between JST and MST?

JST is 16 hours behind MST. JST is UTC+9 and MST is UTC-7.

What is 9 AM JST in MST?

9 AM JST is 6 PM MST (previous day).

What is 12 PM JST in MST?

12 PM JST (noon) is 9 PM MST (previous day).

What are the best meeting times between JST and MST?

There is no standard business hours overlap between JST and MST.

JST to MST Time Converter

Japan Standard Time → Mountain Standard Time

JST

UTC+9

Japan Standard Time

offset

-16h

MST is 16h behind

MST

UTC-7

Mountain Standard Time

MST observes DST — offset shifts ±1h during transitions

Japan Standard Time (JST) is 16 hours behind Mountain Standard Time (MST). When it is noon in JST, it is 9 PM in MST. This offset may change during Daylight Saving Time transitions.

Meeting planner tool Reverse: MST to JST

Cities in JST

🇯🇵Tokyo 🇯🇵Osaka

Cities in MST

🇺🇸Phoenix 🇺🇸Denver 🇨🇦Calgary

All 24 Hours — JST to MST

Click any row to see the full detail page. Current hour in JST is highlighted.

Both business hoursPartial overlap

12 AM6 AM12 PM6 PM11 PM

Best Meeting Times — JST & MST

No standard business-hours overlap between JST and MST. Consider early morning or evening calls.

Challenging overlap

JST and MST are 16 hours apart with no shared business-hours window. Try scheduling at 8 AM in the earlier timezone or 6 PM in the later one.

8 AM→5 PM−1d 9 AM→6 PM−1d 10 AM→7 PM−1d 11 AM→8 PM−1d 12 PM→9 PM−1d 1 PM→10 PM−1d 2 PM→11 PM−1d 3 PM→12 AM 4 PM→1 AM 5 PM→2 AM

Related Time Zone Conversions

Frequently Asked Questions — JST to MST

Japan Standard Time (JST) is 16 hours behind Mountain Standard Time (MST). JST is UTC+9 and MST is UTC-7. This offset may shift by ±1 hour during Daylight Saving Time transitions.