CHST — Chamorro Standard Time
CHST is Chamorro Standard Time, +10:00, used in Oceania. In code, use Pacific/Guam rather than the abbreviation.
Chamorro Standard Time · Oceania
10:15:45
Thursday, 13 August 2026
- abbreviation denotes
- +10:00
- in force right now
- ChST (UTC+10:00)
- use in code
- Pacific/Guam
- next clock change
- none — fixed offset
Right now this zone is on ChST, not CHST —
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("Pacific/Guam"))
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'tCHST questions
What does CHST stand for?
CHST is Chamorro Standard Time, +10:00, used in Oceania. The IANA zone to use in code is Pacific/Guam.
What time is it in CHST right now?
Chamorro Standard Time: 10:15 on Thursday (ChST).
Which IANA timezone should I use instead of CHST?
Pacific/Guam for Chamorro 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 ChST instead of CHST?
Because Pacific/Guam is currently on ChST (UTC+10:00), its daylight-saving variant. CHST (+10:00) applies during the other half of the year. Both names refer to the same place, one hour apart.