HDT to UTC Converter

Updating current time…

No shared working hoursThu, Oct 15

HDT
Hawaii Daylight Time
UTC−9
12am
3am
6am
9am
12pm
3pm
6pm
9pm
HDT is not used on this date
This converter keeps HDT at UTC−9. Honolulu uses HST (UTC−10) on this date. Open the HST converter, or choose Honolulu, Pearl City, or Hilo for city-specific time.
UTC
Coordinated Universal Time
UTC+0
9h ahead
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

Selected conversion

3:00 am03:00 HDT (UTC-9), Oct 15, 2026 = 12:00 pm12:00 UTC (UTC+0), Oct 15, 2026

HDT is 9 hours behind UTC.

HDT and UTC examples

These examples always use HDT (UTC-9) and UTC (UTC+0). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.

HDT is 9 hours behind UTC.

How the time difference changes

HDT is 9 hours behind UTC year-round.

Working hours of 9:00 am to 6:00 pm in HDT correspond to 6:00 pm to 3:00 am (next day) in UTC.Working hours of 09:00 to 18:00 in HDT correspond to 18:00 to 03:00 (next day) in UTC.

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

Time Difference

Hawaii Daylight Time is 9 hours behind Coordinated Universal Time.
3:00 am03:00 in HDT is 12:00 pm12:00 in UTC

HDT to UTC call time
Best time for a conference call or a meeting is between 8:30am-9:30am08:30-09:30 in HDT which corresponds to 5:30pm-6:30pm17:30-18:30 in UTC. Their 9am–6pm09:00–18:00 working hours do not overlap; this is a suggested compromise.

3:00 am03:00 Hawaii Daylight Time (HDT). Offset UTC -9:00 hours
12:00 pm12:00 Coordinated Universal Time (UTC). Offset UTC 0:00 hours

3:00 am03:00 HDT / 12:00 pm12:00 UTC

Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.

Hourly time comparison
HDTUTC
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Hawaii Daylight Time

Offset: HDT is 9 hours behind Greenwich Mean Time (GMT).

Countries using this time zone: United States

Map of the areas on Hawaii Daylight Time (HDT)
HDT part of the year

Today all shaded areas are on HDT.

Open the world time zone map© OpenStreetMap

HDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -09 - basic short
  • -0900 - basic
  • -09:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0900 - sign character (-) followed by a four digit time providing hours (09) and minutes (00) of the offset. Indicates an offset of nine hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Victor - Military abbreviation for HDT
  • V - short form of 'Victor'
IANA/Olson: Reflects HDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Adak
  • America/Atka
  • US/Aleutian
Time zones with the GMT -9 offset:
  • AKST - Alaska Standard Time
  • AHDT - Alaska-Hawaii Daylight Time
  • HADT - Hawaii-Aleutian Daylight Time
  • GAMT - Gambier Time
  • HDT - Hawaii Daylight Time
  • V - Victor Time Zone

Coordinated Universal Time

Offset: UTC is the same as Greenwich Mean Time (GMT).

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

Map of the areas on Coordinated Universal Time (UTC)
UTC all year UTC part of the year

Today some of the lighter areas are on UTC+1 (British Summer Time, Irish Standard Time, WEST).

Open the world time zone map© OpenStreetMap

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 - Coordinated Universal Time
  • WT - Western Sahara Standard Time
  • Z - Zulu Time Zone
EST to ISTGMT to ESTPST to ESTEST to GMTPST to GMT