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India to HST

-15h 30m

India

ISTSOURCE
UTC+05:30
HH12
:
MM00
  
12:00 (24-hr)
12 AM6 AM12 PM6 PM12 AM

HST

HST
UTC-10:00
HH08
:
MM30
  
(previous day)20:30 (24-hr)
12 AM6 AM12 PM6 PM12 AM
India
HST
12:00 AM
8:30 AM-1
2:00 AM
10:30 AM-1
4:00 AM
12:30 PM-1
6:00 AM
2:30 PM-1
8:00 AM
4:30 PM-1
10:00 AM
6:30 PM-1
12:00 PM
8:30 PM-1
2:00 PM
10:30 PM-1
4:00 PM
12:30 AM
6:00 PM
2:30 AM
8:00 PM
4:30 AM
10:00 PM
6:30 AM

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

IST and HST on the World Map

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

ISTHSTMumbaiDelhiBangaloreKolkataHonoluluHiloKailuaPearl City
IST Zone
→
HST Zone

Explore all world timezones interactively →

IST – India Standard Time

UTC+05:30

India Standard Time (IST) is the time zone for India and Sri Lanka, 5 hours and 30 minutes ahead of UTC.

Countries in IST
IndiaSri Lanka
Major Cities in IST
MumbaiDelhiBangaloreKolkataChennaiHyderabadPuneAhmedabadColomboJaipurLucknowSurat
Key Facts about IST
  • •India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT.
  • •India uses a single time zone despite spanning 30° of longitude.
  • •IST is one of only a handful of time zones with a 30-minute offset.
  • •IST is the most populous single time zone in the world with over 1.4 billion people.
  • •The Bombay Stock Exchange (BSE) and National Stock Exchange (NSE) operate on IST.
Daylight Saving:No – UTC+05:30 year-round
Learn more about IST on Wikipedia

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

India vs HST: Offsets, DST and Best Call Times

India runs on India Standard Time (IST) at UTC+05:30. HST runs on Hawaii Standard Time (HST) at UTC-10:00. That puts India 15 hours 30 minutes behind HST — a difference of -15h 30m at the current offsets.

In practice, when it is 9:00 AM in India it is 5:30 PM in HST on the previous day. Midnight in India is 8:30 AM in HST. Neither zone observes daylight saving time, so the offset between them stays constant all year.

India to HST time conversion table

India (IST)HST (HST)Day
12:00 AM8:30 AMprevious day
6:00 AM2:30 PMprevious day
7:00 AM3:30 PMprevious day
8:00 AM4:30 PMprevious day
9:00 AM5:30 PMprevious day
12:00 PM8:30 PMprevious day
3:00 PM11:30 PMprevious day
5:00 PM1:30 AMsame day
6:00 PM2:30 AMsame day
9:00 PM5:30 AMsame day

Why people convert India to HST time

  • Scheduling a call from India to HST: a 10:00 AM start in India lands at 6:30 PM in HST the previous day, so you can confirm the slot without doing the arithmetic yourself.
  • Handling a -15h 30m gap: India and HST 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 HST is 5:30 PM in India.
  • Watching a live event or market open: India viewers need 5:30 PM in HST to catch a 9:00 AM start there, and 3:30 PM if the event is anchored to India.
  • Always state the zone abbreviation, not just the hour. "3:00 PM IST" is unambiguous; "3 PM" across a -15h 30m gap is not.
  • With a -15h 30m gap there is no shared 9-to-5 window, so alternate the early start: one week India takes the early slot, the next week HST does.

About IST (India Standard Time)

India Standard Time (IST) is the time observed throughout India and Sri Lanka. It is based on the 82.5°E meridian, passing through Mirzapur in Uttar Pradesh. India uses a single time zone despite spanning roughly 30° of longitude, which has been debated. IST does not observe daylight saving time. India is the world's most populous country, making IST one of the most-used time zones globally. The IT outsourcing industry and call centers operate primarily on IST, making the EST-to-IST conversion one of the most searched timezone conversions.

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.

Best time to call between India and HST

With a -15h 30m offset there is no overlap inside a normal 9 AM – 5 PM day. HST opens at 9:00 AM HST, which is 5:30 PM in India, so real-time calls need an early-morning or late-evening slot on one side.

Business hours overlap

India and HST have no shared working hours because of the -15h 30m gap. Teams need to alternate early starts or rely on asynchronous handovers.

India is 15 hours 30 minutes behind HST (IST UTC+05:30 → HST UTC-10:00). 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 India and HST?

India (IST, UTC+05:30) is 15 hours 30 minutes behind HST (HST, UTC-10:00). The gap is currently -15h 30m.

How do I convert India time to HST time?

Add -15h 30m to India local time. For example, 9:00 AM in India is 5:30 PM in HST (previous day).

What time is it in HST right now?

HST uses HST at UTC-10:00. Use the live converter at the top of this page — it updates in real time and already accounts for the -15h 30m offset from India.

What is the best time to call HST from India?

There is no shared working-hours window because of the -15h 30m gap. The closest option is 1:00 PM in India, which is 9:30 PM in HST.

Which is behind, India or HST?

India is 15 hours 30 minutes behind HST. When it is 12:00 PM in India it is 8:30 PM in HST.

Do India and HST use different time zones?

India (India) uses IST at UTC+05:30, while HST uses HST at UTC-10:00. The IANA identifiers are Asia/Kolkata and Pacific/Honolulu.

Does daylight saving time affect the India–HST difference?

Neither zone observes daylight saving time, so the -15h 30m offset between India and HST is fixed all year.

Which other cities share India's time zone?

IST also covers Mumbai, Delhi, Bangalore, Kolkata, Chennai, Hyderabad, Pune, Ahmedabad and 4 more.

Which countries use IST, India's zone?

IST is used in India, Sri Lanka.

Is there a day difference between India and HST?

Sometimes. The -15h 30m gap is large enough that 8:00 PM or later in India already falls on the in HST.

What is the time difference between India and HST?

HST is -15h 30m from India.

What timezone is India in?

India operates on its local timezone.

What timezone is HST in?

HST operates on its local timezone.

Which countries use IST (India Standard Time)?

IST is used in India, Sri Lanka.

Does IST observe daylight saving time?

No, IST does not observe daylight saving time and remains at UTC+05:30 year-round.

What are some interesting facts about IST?

India is 10 hours 30 minutes ahead of EST and 5 hours 30 minutes ahead of GMT. India uses a single time zone despite spanning 30° of longitude.

Which cities are in the HST timezone?

Major cities in the HST timezone include Honolulu, Hilo, Kailua, Pearl City, Kapolei.

What is the UTC offset for HST?

Hawaii Standard Time (HST) is at UTC-10:00.

What should I know about the HST timezone?

Hawaii does not observe daylight saving time. HST is 5 hours behind EST in winter and 6 hours behind EDT in summer.

When is it midnight in India, what time is it in HST?

When it is 12:00 AM (midnight) in India (IST), it is -15h 30m later in HST (HST).