Updating current time…
HDT
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.
HST
UTC−10
1h behind
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

Selected conversion

3:00 am03:00 HDT (UTC-9), Oct 15, 2026 = 2:00 am02:00 HST (UTC-10), Oct 15, 2026

HDT is 1 hour ahead of HST.

HDT and HST examples

These examples always use HDT (UTC-9) and HST (UTC-10). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.

HDT is 1 hour ahead of HST.

How the time difference changes

HDT is 1 hour ahead of HST year-round.

Working hours of 9:00 am to 6:00 pm in HDT correspond to 8:00 am to 5:00 pm in HST.Working hours of 09:00 to 18:00 in HDT correspond to 08:00 to 17:00 in HST.

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

Time Difference

Hawaii Daylight Time is 1 hour ahead of Hawaii Standard Time.
3:00 am03:00 in HDT is 2:00 am02:00 in HST

HDT to HST call time
Best time for a conference call or a meeting is between 10am-6pm10:00-18:00 in HDT which corresponds to 9am-5pm09:00-17:00 in HST

3:00 am03:00 Hawaii Daylight Time (HDT). Offset UTC -9:00 hours
2:00 am02:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours

3:00 am03:00 HDT / 2:00 am02:00 HST

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
HDTHST
11:00pm previous day
12:00am
1:00am
2:00am
3:00am
4:00am
5:00am
6:00am
7:00am
8:00am
9:00am
10:00am
11:00am
12:00pm
1:00pm
2:00pm
3:00pm
4:00pm
5:00pm
6:00pm
7:00pm
8:00pm
9:00pm
10:00pm
23:00 previous day
00:00
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00

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.

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

Hawaii Standard Time

Offset: HST is 10 hours behind Greenwich Mean Time (GMT).

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 350,964 people. Other major cities in this time zone include Pearl City, Hilo, Kailua, Waipahu.

Daylight Saving: Some places on Hawaii Standard Time (HST) keep the same time all year, while others use HST for only part of the year and change their clocks for daylight saving time; see upcoming clock changes worldwide.

Map of the areas on Hawaii Standard Time (HST)
HST all year HST part of the year

Today the lighter areas are on UTC−9 (HDT).

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