HST to CAT
+12hHST
HSTSOURCECAT
CATGreen rows indicate typical business hours (9 AM - 5 PM)
HST and CAT on the World Map
The map below highlights the HST (Hawaii Standard Time) and CAT (Central Africa Time) timezone regions across the globe.
HST – Hawaii Standard Time
UTC-10:00Hawaii Standard Time (HST) is the time zone for the Hawaiian Islands, 10 hours behind UTC.
- •Hawaii does not observe daylight saving time.
- •HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.
- •Hawaii is one of only two US states that don't observe DST (the other is Arizona).
CAT – Central Africa Time
UTC+02:00Central Africa Time (CAT, UTC+02:00) covers Zimbabwe, Zambia, Mozambique, Malawi and neighbouring countries.
- •Central Africa Time is fixed at UTC+02:00 with no daylight saving.
- •CAT matches South Africa Standard Time (SAST) all year.
- •It is the same offset as Central European Time in winter.
- •Harare is level with Johannesburg and one hour ahead of Lagos.
Comparing Time Zones: HST and CAT
HST runs on Hawaii Standard Time (HST) at UTC-10:00. CAT runs on Central Africa Time (CAT) at UTC+02:00. That puts HST 12 hours ahead of CAT — a difference of +12h at the current offsets.
In practice, when it is 9:00 AM in HST it is 9:00 PM in CAT. Midnight in HST is 12:00 PM in CAT. Neither zone observes daylight saving time, so the offset between them stays constant all year.
HST to CAT time conversion table
| HST (HST) | CAT (CAT) | Day |
|---|---|---|
| 12:00 AM | 12:00 PM | same day |
| 6:00 AM | 6:00 PM | same day |
| 7:00 AM | 7:00 PM | same day |
| 8:00 AM | 8:00 PM | same day |
| 9:00 AM | 9:00 PM | same day |
| 12:00 PM | 12:00 AM | next day |
| 3:00 PM | 3:00 AM | next day |
| 5:00 PM | 5:00 AM | next day |
| 6:00 PM | 6:00 AM | next day |
| 9:00 PM | 9:00 AM | next day |
Why people convert HST to CAT time
- Scheduling a call from HST to CAT: a 10:00 AM start in HST lands at 10:00 PM in CAT, so you can confirm the slot without doing the arithmetic yourself.
- Handling a +12h gap: HST and CAT have no overlap inside a normal 9-to-5 day, so real-time meetings need an early-morning or late-evening slot on one side. 9:00 AM in CAT is 9:00 PM in HST.
- Keeping family and friends in sync: knowing that 8:00 PM in HST is 8:00 AM in CAT makes it easy to avoid calling at 3 AM.
- Always state the zone abbreviation, not just the hour. "3:00 PM HST" is unambiguous; "3 PM" across a +12h gap is not.
- With a +12h gap there is no shared 9-to-5 window, so alternate the early start: one week HST takes the early slot, the next week CAT does.
About HST (Hawaii Standard Time)
Hawaii Standard Time (HST) is used in the state of Hawaii and does not observe daylight saving time. This makes HST one of the most consistent time zones in the US. The Hawaiian Islands are among the last places on Earth to see a new calendar day.
About CAT (Central Africa Time)
Central Africa Time (CAT) is fixed at UTC+02:00 all year across a broad belt of southern and central Africa, including Zimbabwe, Zambia, Mozambique, Malawi, Rwanda, Burundi and the eastern Democratic Republic of the Congo. None of these countries observes daylight saving time, so CAT never shifts. It is the same offset as South Africa Standard Time (SAST) and the winter version of Central European Time, which makes CAT a convenient bridge between African, European and Middle Eastern schedules — Harare is level with Johannesburg all year and one hour ahead of Lagos.
Best time to call between HST and CAT
With a +12h offset there is no overlap inside a normal 9 AM – 5 PM day. CAT opens at 9:00 AM CAT, which is 9:00 PM in HST, so real-time calls need an early-morning or late-evening slot on one side.
Business hours overlap
HST and CAT have no shared working hours because of the +12h gap. Teams need to alternate early starts or rely on asynchronous handovers.
HST is 12 hours ahead of CAT (HST UTC-10:00 → CAT UTC+02:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.
Learn More About Time
Dive deeper into the fascinating world of timekeeping, time zones, and how they shape our global society:
Frequently Asked Questions
What is the time difference between HST and CAT?
HST (HST, UTC-10:00) is 12 hours ahead of CAT (CAT, UTC+02:00). The gap is currently +12h.
How do I convert HST time to CAT time?
Add +12h to HST local time. For example, 9:00 AM in HST is 9:00 PM in CAT.
What time is it in CAT right now?
CAT uses CAT at UTC+02:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +12h offset from HST.
What is the best time to call CAT from HST?
There is no shared working-hours window because of the +12h gap. The closest option is 1:00 PM in HST, which is 1:00 AM in CAT.
Which is ahead, HST or CAT?
HST is 12 hours ahead of CAT. When it is 12:00 PM in HST it is 12:00 AM in CAT.
Does daylight saving time affect the HST–CAT difference?
Neither zone observes daylight saving time, so the +12h offset between HST and CAT is fixed all year.
Which other cities share HST's time zone?
HST also covers Honolulu, Hilo, Kailua, Pearl City, Kapolei.
Which countries use HST, HST's zone?
HST is used in United States (Hawaii).
Is there a day difference between HST and CAT?
Sometimes. The +12h gap is large enough that 8:00 PM or later in HST already falls on the next day in CAT.
What is the time difference between HST and CAT?
CAT is +12h from HST.
What timezone is HST in?
HST operates on its local timezone.
What timezone is CAT in?
CAT operates on its local timezone.
Which countries use HST (Hawaii Standard Time)?
HST is used in United States (Hawaii).
Does HST observe daylight saving time?
No, HST does not observe daylight saving time and remains at UTC-10:00 year-round.
What are some interesting facts about HST?
Hawaii does not observe daylight saving time. HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.
Which cities are in the CAT timezone?
Major cities in the CAT timezone include Harare, Lusaka, Maputo, Lilongwe, Kigali.
What is the UTC offset for CAT?
Central Africa Time (CAT) is at UTC+02:00.
What should I know about the CAT timezone?
Central Africa Time is fixed at UTC+02:00 with no daylight saving. CAT matches South Africa Standard Time (SAST) all year.
When is it midnight in HST, what time is it in CAT?
When it is 12:00 AM (midnight) in HST (HST), it is +12h later in CAT (CAT).
Related Developer Tools
Explore more tools that work great with timezone conversions for international teams:
Related Timezone Conversions
More HST time conversions
- hst to honolulu
- hst to new york
- hst to london
- hst to dubai
- hst to tokyo
- hst to singapore
- hst to sydney
- hst to los angeles
- hst to paris
- hst to delhi
- hst to mumbai
- hst to berlin
- hst to hong kong
- hst to toronto
- hst to kathmandu
- new york to hst
- london to hst
- dubai to hst
- tokyo to hst
- singapore to hst
- sydney to hst
- los angeles to hst
- paris to hst
- delhi to hst
- mumbai to hst
- berlin to hst
- hong kong to hst
- toronto to hst
- kathmandu to hst
See every conversion from HST →·See every conversion from CAT →