JST to MST Converter

Mountain Time (MST / MDT) is 15 hours behind Japan Time (JST).

Quick Reference

Japan Time
JST (GMT+9)

No Daylight Saving Time

Mountain Time
MDT (GMT-6)

MST starts on Nov 1, 2026

Frequently Asked Questions

What is the difference between JST and MST?
MST is 15 hours behind JST.
How do I convert JST to MST?
To convert from JST to MST, subtract 15 hours. Use the interactive converter on this page to convert specific times.
What cities are in JST and MST?
Cities in JST include Tokyo, Yokohama, Osaka, Nagoya, Sapporo. Cities in MST include Denver, El Paso, Albuquerque, Colorado Springs, Salt Lake City.
JST to MST Converter | Timezone App