HST
Hawaii Standard Time
GMT -10
12am
3am
6am
9am
12pm
3pm
6pm
9pm
UTC
Universal Time Coordinated
GMT +0
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

HST is 10 hours behind UTC. HST uses GMT -10, and UTC uses GMT +0 for this comparison.

For example, 2:00 am HST is 12:00 pm UTC. Use the converter above to adjust the date or time and create a shareable meeting link.

Best meeting overlap: 7:30am-8:30am HST, which is 5:30pm-6:30pm UTC.

Compare HST time with UTC time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.

Time Difference

Hawaii Standard Time is 10 hours behind Universal Time Coordinated
2:00 am02:00 in HST is 12:00 pm12:00 in UTC

HST to UTC call time
Best time for a conference call or a meeting is between 7:30am-8:30am in HST which corresponds to 5:30pm-6:30pm in UTC

2:00 am02:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours
12:00 pm12:00 Universal Time Coordinated (UTC). Offset UTC 0:00 hours

2:00 am02:00 HST / 12:00 pm12:00 UTC

HSTUTC
12am (midnight)10am
1am11am
2am12pm (noon)
3am1pm
4am2pm
5am3pm
6am4pm
7am5pm
8am6pm
9am7pm
10am8pm
11am9pm
12pm (noon)10pm
1pm11pm
2pm12am (midnight)
3pm1am
4pm2am
5pm3am
6pm4am
7pm5am
8pm6am
9pm7am
10pm8am
11pm9am
00:0010:00
01:0011:00
02:0012:00
03:0013:00
04:0014:00
05:0015:00
06:0016:00
07:0017:00
08:0018:00
09:0019:00
10:0020:00
11:0021:00
12:0022:00
13:0023:00
14:0000:00
15:0001:00
16:0002:00
17:0003:00
18:0004:00
19:0005:00
20:0006:00
21:0007:00
22:0008:00
23:0009:00

Hawaii Standard Time

Offset: HST is 10 hours behind Greenwich Mean Time (GMT) and is used in Pacific

Countries using this time zone: United States

Principal Cities: The largest city in the HST time zone is Honolulu in the United States, with about 371,657 people. Other major cities in this time zone include Pearl City, Hilo, Kailua, Waipahu.

Daylight Saving: Clocks in Hawaii Standard Time (HST) do not change for daylight saving time, so HST stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter.

HST Time Zone Geo Map
HST timezone map

HST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -10 - basic short
  • -1000 - basic
  • -10:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -1000 - sign character (-) followed by a four digit time providing hours (10) and minutes (00) of the offset. Indicates an offset of ten hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Whiskey - Military abbreviation for HST
  • W - short form of 'Whiskey'
IANA/Olson: Reflects HST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Adak
  • America/Atka
  • HST
  • Pacific/Honolulu
  • Pacific/Johnston
  • US/Aleutian
  • US/Hawaii
Time zones with the GMT -10 offset:
  • HAST - Hawaii-Aleutian Standard Time
  • CKT - Cook Island Time
  • HST - Hawaii Standard Time
  • TAHT - Tahiti Time
  • W - Whiskey Time Zone

Universal Time Coordinated

Offset: UTC is 0 hours ahead Greenwich Mean Time (GMT) and is used in Universal

Coordinated Universal Time (UTC) is the world time standard that regulates clocks and time. It is successor to Greenwich Mean Time (GMT). For casual use, UTC is the same as GMT, but is used by the scientific community.
UTC is the time standard commonly used across the world since 1972. It is used in many technical fields, like aviation industry and meteorologists, also used to synchronize time across internet networks.

UTC representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • Z - is the zone designator for the zero UTC/GMT offset, also known as 'Zulu' time
  • +00 - basic short
  • +0000 - basic
  • +00:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0000 - sign character (+) followed by a four digit time providing hours (00) and minutes (00) of the offset. Indicates the zero UTC/GMT offset.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Zulu - Military abbreviation for UTC
  • Z - short form of 'Zulu'
IANA/Olson: Reflects UTC time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Etc/UCT
  • Etc/UTC
  • Etc/Universal
  • Etc/Zulu
  • UCT
  • UTC
  • Universal
  • Zulu
Time zones with the GMT +0 offset:
  • EGST - Eastern Greenland Summer Time
  • GMT - Greenwich Mean Time
  • WET - Western European Time
  • AZOST - Azores Summer Time
  • UTC - Universal Time Coordinated
  • WT - Western Sahara Standard Time
  • Z - Zulu Time Zone