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Honolulu to South Korea

+19h

Honolulu

HSTSOURCE
USA · UTC-10:00
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

South Korea

KST
UTC+09:00
HH07
:
MM00
  
(next day)07:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM
Honolulu
South Korea
12:00 AM
7:00 PM
2:00 AM
9:00 PM
4:00 AM
11:00 PM
6:00 AM
1:00 AM+1
8:00 AM
3:00 AM+1
10:00 AM
5:00 AM+1
12:00 PM
7:00 AM+1
2:00 PM
9:00 AM+1
4:00 PM
11:00 AM+1
6:00 PM
1:00 PM+1
8:00 PM
3:00 PM+1
10:00 PM
5:00 PM+1

Green rows indicate typical business hours (9 AM - 5 PM)

HST and KST on the World Map

The map below highlights the HST (Hawaii Standard Time) and KST (Korea Standard Time) timezone regions across the globe.

HSTKSTHonoluluHiloKailuaPearl CitySeoulBusanIncheonDaegu
HST Zone
→
KST Zone

Explore all world timezones interactively →

HST – Hawaii Standard Time

UTC-10:00

Hawaii Standard Time (HST) is the time zone for the Hawaiian Islands, 10 hours behind UTC.

Countries in HST
United States (Hawaii)
Major Cities in HST
HonoluluHiloKailuaPearl CityKapolei
Key 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.
  • •Hawaii is one of only two US states that don't observe DST (the other is Arizona).
Daylight Saving:No – UTC-10:00 year-round
Learn more about HST on Wikipedia

KST – Korea Standard Time

UTC+09:00

Korea Standard Time (KST) is the time zone for South Korea, 9 hours ahead of UTC.

Countries in KST
South KoreaNorth Korea
Major Cities in KST
SeoulBusanIncheonDaeguDaejeonPyongyang
Key Facts about KST
  • •South Korea does not observe daylight saving time.
  • •Seoul is home to Samsung, LG, and Hyundai headquarters.
  • •KST is the same offset as JST (UTC+09:00).
Daylight Saving:No – UTC+09:00 year-round
Learn more about KST on Wikipedia

About Honolulu

Wikipedia

Honolulu operates on Hawaii Standard Time (HST), UTC-10 with no daylight saving. Hawaii's consistent time makes it a predictable connection between Asia and mainland USA.

Population:350,000
Metro:1 million
Business Hours:8:00 AM - 5:00 PM HST
Currency:USD ($)
Key Landmarks
Waikiki BeachDiamond HeadPearl HarborIolani PalaceHanauma Bay
Did You Know?

Pearl Harbor memorial receives over 2 million visitors annually.

Learn more about HST timezone →

Understanding the +19h Gap: Honolulu vs South Korea

Honolulu runs on Hawaii-Aleutian Standard Time (HST) at UTC-10:00. South Korea runs on Korean Standard Time (KST) at UTC+09:00. That puts Honolulu 19 hours ahead of South Korea — a difference of +19h at the current offsets.

In practice, when it is 9:00 AM in Honolulu it is 4:00 AM in South Korea on the next day. Midnight in Honolulu is 7:00 PM in South Korea. Neither zone observes daylight saving time, so the offset between them stays constant all year.

Honolulu to South Korea time conversion table

Honolulu (HST)South Korea (KST)Day
12:00 AM7:00 PMsame day
6:00 AM1:00 AMnext day
7:00 AM2:00 AMnext day
8:00 AM3:00 AMnext day
9:00 AM4:00 AMnext day
12:00 PM7:00 AMnext day
3:00 PM10:00 AMnext day
5:00 PM12:00 PMnext day
6:00 PM1:00 PMnext day
9:00 PM4:00 PMnext day

Why people convert Honolulu to South Korea time

  • Scheduling a call from Honolulu to South Korea: a 10:00 AM start in Honolulu lands at 5:00 AM in South Korea the next day, so you can confirm the slot without doing the arithmetic yourself.
  • Handling a +19h gap: Honolulu and South Korea 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 South Korea is 4:00 AM in Honolulu.
  • Booking travel or deliveries: tracking South Korea local time against Honolulu keeps pickup windows and arrival estimates honest across the +19h offset.
  • Always state the zone abbreviation, not just the hour. "3:00 PM HST" is unambiguous; "3 PM" across a +19h gap is not.
  • With a +19h gap there is no shared 9-to-5 window, so alternate the early start: one week Honolulu takes the early slot, the next week South Korea 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 KST (Korea Standard Time)

Korea Standard Time (KST) is the time zone used in South Korea. It shares the same UTC offset as Japan Standard Time but is a distinct time zone. South Korea does not observe daylight saving time. Seoul, the capital, is a major global tech and business hub.

Best time to call between Honolulu and South Korea

With a +19h offset there is no overlap inside a normal 9 AM – 5 PM day. South Korea opens at 9:00 AM KST, which is 4:00 AM in Honolulu, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

Honolulu and South Korea have no shared working hours because of the +19h gap. Teams need to alternate early starts or rely on asynchronous handovers.

Honolulu is 19 hours ahead of South Korea (HST UTC-10:00 → KST UTC+09:00). There is no shared 9-to-5 window, so plan around an early or late slot. Remember to re-check around daylight-saving transitions.

Frequently Asked Questions

What is the time difference between Honolulu and South Korea?

Honolulu (HST, UTC-10:00) is 19 hours ahead of South Korea (KST, UTC+09:00). The gap is currently +19h.

How do I convert Honolulu time to South Korea time?

Add +19h to Honolulu local time. For example, 9:00 AM in Honolulu is 4:00 AM in South Korea (next day).

What time is it in South Korea right now?

South Korea uses KST at UTC+09:00. Use the live converter at the top of this page — it updates in real time and already accounts for the +19h offset from Honolulu.

What is the best time to call South Korea from Honolulu?

There is no shared working-hours window because of the +19h gap. The closest option is 1:00 PM in Honolulu, which is 8:00 AM in South Korea.

Which is ahead, Honolulu or South Korea?

Honolulu is 19 hours ahead of South Korea. When it is 12:00 PM in Honolulu it is 7:00 AM in South Korea.

Do Honolulu and South Korea use different time zones?

Honolulu (USA) uses HST at UTC-10:00, while South Korea (South Korea) uses KST at UTC+09:00. The IANA identifiers are Pacific/Honolulu and Asia/Seoul.

Does daylight saving time affect the Honolulu–South Korea difference?

Neither zone observes daylight saving time, so the +19h offset between Honolulu and South Korea is fixed all year.

Which other cities share Honolulu's time zone?

HST also covers Honolulu, Hilo, Kailua, Pearl City, Kapolei.

Which countries use HST, Honolulu's zone?

HST is used in United States (Hawaii).

Is there a day difference between Honolulu and South Korea?

Sometimes. The +19h gap is large enough that 8:00 PM or later in Honolulu already falls on the next day in South Korea.

What is the time difference between Honolulu and South Korea?

South Korea is +19h from Honolulu.

What timezone is Honolulu in?

Honolulu operates on Hawaii Standard Time (HST), UTC-10 with no daylight saving. Hawaii's consistent time makes it a predictable connection between Asia and mainland USA.

What timezone is South Korea in?

South Korea operates on its local timezone.

What are the business hours in Honolulu?

Standard business hours in Honolulu are 8:00 AM - 5:00 PM HST.

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 KST timezone?

Major cities in the KST timezone include Seoul, Busan, Incheon, Daegu, Daejeon, Pyongyang.

What is the UTC offset for KST?

Korea Standard Time (KST) is at UTC+09:00.

What should I know about the KST timezone?

South Korea does not observe daylight saving time. Seoul is home to Samsung, LG, and Hyundai headquarters.

When is it midnight in Honolulu, what time is it in South Korea?

When it is 12:00 AM (midnight) in Honolulu (HST), it is +19h later in South Korea (KST).