MST — which one do you mean?
MST means 2 different things, and they are
hours apart. If you received a timestamp labelled MST, the sender's
location decides which of these applies — pick it below.
Mountain Standard Time · North America
18:26:03
Wednesday, 12 August 2026
- abbreviation denotes
- -07:00
- in force right now
- MDT (UTC-06:00) · DST
- use in code
- America/Denver
- also valid
- America/Phoenix, America/Edmonton
- next clock change
- 1 Nov 2026 01:00 → MST
Arizona (America/Phoenix) stays on MST all year.
Right now this zone is on MDT, not MST —
they are the same place at different times of year.
Myanmar Standard Time · Asia
06:56:03
Thursday, 13 August 2026
- abbreviation denotes
- +06:30
- in force right now
- UTC+06:30 (UTC+06:30)
- use in code
- Asia/Yangon
- next clock change
- none — fixed offset
UTC+6:30 — a half-hour offset, unrelated to the US zone.
Right now this zone is on UTC+06:30, not MST —
they are the same place at different times of year.
Use the IANA name, not the abbreviation
Python
from datetime import datetime
from zoneinfo import ZoneInfo
# right: an IANA zone carries the full history of rule changes
now = datetime.now(ZoneInfo("America/Denver"))
print(now.isoformat(), now.tzname())
# wrong: an abbreviation is not resolvable, and a hard-coded offset
# silently rots the next time the rules change
# now = datetime.now(timezone(timedelta(hours=...))) # don'tMST questions
What does MST stand for?
MST has 2 distinct meanings in active use: Mountain Standard Time (-07:00, America/Denver); Myanmar Standard Time (+06:30, Asia/Yangon). Which one applies depends entirely on who wrote the timestamp.
What time is it in MST right now?
Mountain Standard Time: 18:26 on Wednesday (MDT); Myanmar Standard Time: 06:56 on Thursday (UTC+06:30).
Which IANA timezone should I use instead of MST?
America/Denver for Mountain Standard Time, Asia/Yangon for Myanmar Standard Time. Date libraries cannot resolve bare abbreviations, and an abbreviation carries no daylight-saving history, so a stored offset silently rots when a government changes the rules.
Why does my computer show MDT instead of MST?
Because America/Denver is currently on MDT (UTC-06:00), its daylight-saving variant. MST (-07:00) applies during the other half of the year. Both names refer to the same place, one hour apart.