JST
Japan Standard Time
GMT +9
12am
3am
6am
9am
12pm
3pm
6pm
9pm
MST/MDT
Mountain Standard Time
GMT -7
12am
3am
6am
9am
12pm
3pm
6pm
9pm
MDT is not used on this date
This converter uses MST (GMT -7), the offset Denver uses on this date. Open the MST converter.

Compare JST time with MDT time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.

Time Difference

Japan Standard Time is 16 hours ahead of Mountain Standard Time
9:00 pm21:00 in JST is 5:00 am05:00 in MST

JST to MST call time
Best time for a conference call or a meeting is between 8:30am-9:30am in JST which corresponds to 4:30pm-5:30pm in MST (previous day)

9:00 pm21:00 Japan Standard Time (JST). Offset UTC +9:00 hours
5:00 am05:00 Mountain Standard Time (MST). Offset UTC -7:00 hours

9:00 pm21:00 JST / 5:00 am05:00 MST

JSTMST
12am (midnight)8am
1am9am
2am10am
3am11am
4am12pm (noon)
5am1pm
6am2pm
7am3pm
8am4pm
9am5pm
10am6pm
11am7pm
12pm (noon)8pm
1pm9pm
2pm10pm
3pm11pm
4pm12am (midnight)
5pm1am
6pm2am
7pm3am
8pm4am
9pm5am
10pm6am
11pm7am
00:0008:00
01:0009:00
02:0010:00
03:0011:00
04:0012:00
05:0013:00
06:0014:00
07:0015:00
08:0016:00
09:0017:00
10:0018:00
11:0019:00
12:0020:00
13:0021:00
14:0022:00
15:0023:00
16:0000:00
17:0001:00
18:0002:00
19:0003:00
20:0004:00
21:0005:00
22:0006:00
23:0007:00

Japan Standard Time

Offset: JST is 9 hours ahead Greenwich Mean Time (GMT) and is used in Asia

Countries using this time zone: Japan

Principal Cities: The largest city in the JST time zone is Tokyo in Japan, with about 8.337 million people. Other major cities in this time zone include Yokohama, Osaka shi, Nagoya shi, Sapporo.

Daylight Saving: Clocks in Japan Standard Time (JST) do not change for daylight saving time, so JST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

JST Time Zone Geo Map
JST timezone map

JST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +09 - basic short
  • +0900 - basic
  • +09:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0900 - sign character (+) followed by a four digit time providing hours (09) and minutes (00) of the offset. Indicates an offset of nine hours to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • India - Military abbreviation for JST
  • I - short form of 'India'
IANA/Olson: Reflects JST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Asia/Tokyo
  • Japan
Time zones with the GMT +9 offset:
  • AWDT - Australian Western Daylight Time
  • CHOST - Choibalsan Summer Time
  • I - India Time Zone
  • IRKST - Irkutsk Summer Time
  • JST - Japan Standard Time
  • KST - Korea Standard Time
  • PWT - Palau Time
  • TLT - East Timor Time
  • ULAST - Ulaanbaatar Summer Time
  • WIT - Eastern Indonesian Time
  • YAKT - Yakutsk Time

Mountain Daylight Time

Offset: MDT is 6 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries using this time zone: Canada, Mexico, United States

Principal Cities: The largest city in the MDT time zone is Calgary in Canada, with about 1.02 million people. Other major cities in this time zone include Edmonton, El Paso, Denver, Albuquerque.

French: HAR - Heure Avancée des Rocheuses

Spanish: MT - Zona Pacífico

MDT Time Zone Geo Map
MDT timezone map

Daylight Saving: Mountain Daylight Time (MDT) is a daylight saving/summer time zone, but some places set clocks back one hour during winter and observe Mountain Standard Time (MST).

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Mountain Daylight Time (MDT) ended on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am local standard time instead. Daylight saving ends annually on the first Sunday of November

Daylight saving time clock moves back for one hour from 2am to 1amStart: Mountain Daylight Time (MDT) starts on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am. Daylight saving starts annually on the second Sunday of March

MDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -06 - basic short
  • -0600 - basic
  • -06:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0600 - sign character (-) followed by a four digit time providing hours (06) and minutes (00) of the offset. Indicates an offset of six hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Sierra - Military abbreviation for MDT
  • S - short form of 'Sierra'
IANA/Olson: Reflects MDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Boise
  • America/Cambridge_Bay
  • America/Ciudad_Juarez
  • America/Denver
  • America/Edmonton
  • America/Inuvik
  • America/Shiprock
  • America/Yellowknife
  • Canada/Mountain
  • MST7MDT
  • Navajo
  • US/Mountain
Time zones with the GMT -6 offset:
  • CST - Central Standard Time
  • CT - Central Time
  • MDT - Mountain Daylight Time
  • EAST - Easter Island Standard Time
  • GALT - Galapagos Time
  • S - Sierra Time Zone