HST/HDT
Hawaii Standard Time
GMT -10
HDT automatically adjusted to HST time zone, that is in use
HAST
Hawaii-Aleutian Standard Time
GMT -10

Time Difference

Hawaii Standard Time is 0 hours ahead of Hawaii-Aleutian Standard Time
7:00 pm19:00 in HST is 7:00 pm19:00 in HAST

HDT to HAST call time
Best time for a conference call or a meeting is between 9am-6pm in HDT which corresponds to 8am-5pm in HAST

7:00 pm19:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours
7:00 pm19:00 Hawaii-Aleutian Standard Time (HAST). Offset UTC -10:00 hours

7:00 pm19:00 HST / 7:00 pm19:00 HAST

HST HAST
12am (midnight) 12am (midnight)
1am 1am
2am 2am
3am 3am
4am 4am
5am 5am
6am 6am
7am 7am
8am 8am
9am 9am
10am 10am
11am 11am
12pm (noon) 12pm (noon)
1pm 1pm
2pm 2pm
3pm 3pm
4pm 4pm
5pm 5pm
6pm 6pm
7pm 7pm
8pm 8pm
9pm 9pm
10pm 10pm
11pm 11pm
0:00 0:00
1:00 1:00
2:00 2:00
3:00 3:00
4:00 4:00
5:00 5:00
6:00 6:00
7:00 7:00
8:00 8:00
9:00 9:00
10:00 10:00
11:00 11:00
12:00 12:00
13:00 13:00
14:00 14:00
15:00 15:00
16:00 16:00
17:00 17:00
18:00 18:00
19:00 19:00
20:00 20:00
21:00 21:00
22:00 22:00
23:00 23:00

Hawaii Daylight Time

Offset: HDT is 9 hours behind Greenwich Mean Time (GMT) and is used in Pacific

Countries: It is used in following countries: United States

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 nine hour and zero minutes time differences 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-Aleutian Standard Time

Offset: HAST is 10 hours behind Greenwich Mean Time (GMT) and is used in North America

HAST 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 ten hour and zero minutes time differences to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Whiskey - Military abbreviation for HAST
  • W - short form of 'Whiskey'
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