Offset
The time difference between Mountain Time and Western Indonesia Time is 13 hours.
Mountain Time (MDT) is behind Western Indonesia Time (WIB).
MDT: UTC-6
WIB: UTC+7
Mountain Time is currently observing daylight saving time; Western Indonesia Time is not.
When to schedule
Standard business hours (9 AM–5 PM, Mon–Fri) in Mountain Time and Western Indonesia Time don't overlap on the same weekday. Western Indonesia Time is 13 hours ahead of Mountain Time.
With some flexibility, there’s a workable window outside standard hours:
- 6 PM–8 PM in Mountain Time (7 AM–9 AM the next day in Western Indonesia Time) — suggest 7:00 PM Mountain Time (8:00 AM Western Indonesia Time).
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
Indonesia
- New Year's DayThu, Jan 1
- Good FridayFri, Apr 3
- Easter SundaySun, Apr 5
- Labour DayFri, May 1
- Ascension DayThu, May 14
- Pancasila DayMon, Jun 1
- Independence DayMon, Aug 17
- Christmas DayFri, Dec 25
About these zones
Mountain Time is also known as MST, or MDT. To call United States, dial +1.
Western Indonesia Time is also known as WIB. To call Indonesia, dial +62.
Western Indonesia Time is approximately 9,400 miles northwest of Mountain Time.
Quick reference
Full 24-hour conversion table — tap any time to open it in the converter.
| MST | WIB | Day |
|---|---|---|
| 12:00 am | 1:00 pm | Same day |
| 1:00 am | 2:00 pm | Same day |
| 2:00 am | 3:00 pm | Same day |
| 3:00 am | 4:00 pm | Same day |
| 4:00 am | 5:00 pm | Same day |
| 5:00 am | 6:00 pm | Same day |
| 6:00 am | 7:00 pm | Same day |
| 7:00 am | 8:00 pm | Same day |
| 8:00 am | 9:00 pm | Same day |
| 9:00 am | 10:00 pm | Same day |
| 10:00 am | 11:00 pm | Same day |
| 11:00 am | 12:00 am | +1 day |
| 12:00 pm | 1:00 am | +1 day |
| 1:00 pm | 2:00 am | +1 day |
| 2:00 pm | 3:00 am | +1 day |
| 3:00 pm | 4:00 am | +1 day |
| 4:00 pm | 5:00 am | +1 day |
| 5:00 pm | 6:00 am | +1 day |
| 6:00 pm | 7:00 am | +1 day |
| 7:00 pm | 8:00 am | +1 day |
| 8:00 pm | 9:00 am | +1 day |
| 9:00 pm | 10:00 am | +1 day |
| 10:00 pm | 11:00 am | +1 day |
| 11:00 pm | 12:00 pm | +1 day |
Daylight saving time
Mountain Time observes daylight saving time; Western Indonesia 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.
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 51m
- Sunrise
- 5:59 AM
- Sunset
- 5:45 PM
- Day length
- 11h 47m
Daylight overlap: 3h 26m — 4:59 PM–8:25 PM in Mountain Time (5:59 AM–9:25 AM in Western Indonesia Time). Both locations are in daylight during this window.
Cities in these zones
Cities in Mountain Time
Cities in Western Indonesia 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 Western Indonesia Time
- CGK
- HLP
- SUB
- BDO
- KNO
- PLM
- SRG
Related conversions
Common conversions
- What is 9:00 am MST in WIB?
- 9:00 am MST is 10:00 pm WIB.
- What is 12:00 pm MST in WIB?
- 12:00 pm MST is 1:00 am WIB, the next day.
- What is 12:30 pm MST in WIB?
- 12:30 pm MST is 1:30 am WIB, the next day.
- What is 2:00 pm MST in WIB?
- 2:00 pm MST is 3:00 am WIB, the next day.
- What is 5:00 pm MST in WIB?
- 5:00 pm MST is 6:00 am WIB, the next day.
- What is 11:30 pm MST in WIB?
- 11:30 pm MST is 12:30 pm WIB, the next day.