IANA tz database · zone identifier
Pacific/Rarotonga
The IANA tz database identifier for Cook Islands Standard Time in Cook Islands. Store this string — not the abbreviation, not the offset — and your timestamps stay correct forever.
Current offset
UTC-10:00
same year-round
Abbreviation
-10
tzdb uses numeric abbreviations here
DST behaviour
Never
has never observed daylight saving
Using this identifier
The string to put in your code.
Pacific/Rarotonga is the identifier to use in code and config for this region. Every modern language, database, and OS resolves it through the same tz database, so the examples here behave identically everywhere.
Avoid storing -10 or -10:00 — abbreviations are ambiguous and fixed offsets can't follow rule changes.
Offset & DST behaviour
35 years.
Pacific/Rarotonga has kept UTC-10:00 year-round since 2 March 1991 — no daylight saving and no offset changes on record since. It is among the most stable identifiers in the database.
Every offset this zone has kept
Keeping this offset since
2 March 1991
Next transition
None scheduled
no DST rules exist for this zone
Safe to assume
Local = UTC − 10h, always
…but store the identifier anyway
Technical record
The database entry, in full.
source: IANA tz database
Where it applies
All of Cook Islands, one clock.
Looking for travel-friendly info? See Avarua or Cook Islands Standard Time.
Related identifiers
Nearby in the database.
Same offset · UTC-10:00
other zones keeping this offset right now
Frequently asked questions
Answers specific to this identifier — generated from the database record. Can't find what you need? Email [email protected].
- What UTC offset is Pacific/Rarotonga?
- Pacific/Rarotonga is UTC-10:00, year-round. The offset never changes because the zone does not observe daylight saving time.
- Does Pacific/Rarotonga observe daylight saving time?
- No. Pacific/Rarotonga has never observed DST — it has kept UTC-10:00 continuously since 2 March 1991.
- Which country uses Pacific/Rarotonga?
- Cook Islands. The identifier covers the whole country.
- Is Pacific/Rarotonga the same as CIST?
- Pacific/Rarotonga is one of the IANA zones that keeps Cook Islands Standard Time (CIST). Use Pacific/Rarotonga in software — CIST is a human-friendly label, not a valid identifier.
Free · Developer API
This zone, as JSON.
Everything on this page — offset, abbreviation, DST rules, coordinates — from one endpoint, always current with the latest tzdb release.
countries, cities, convert, DST transitions coming next.
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