HADT to HAST Converter
HADT is not used on this date
This converter uses HST (GMT -10), the offset Adak uses on this date. Open the HST converter.Quick answers
Selected conversion
The selected date and time will appear here when the converter loads.
HADT and HAST examples
These examples always use HADT (UTC-9) and HAST (UTC-10). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.
HADT is 1 hour ahead of HAST.
How the time difference changes
For most of the year, HADT is 1 hour ahead of HAST. At other times of the year, HST and HAST have the same time.
For most of the year, working hours of 9:00 am to 5:00 pm in HADT correspond to 8:00 am to 4:00 pm in HAST. At other times of the year, working hours of 9:00 am to 5:00 pm in HST correspond to 9:00 am to 5:00 pm in HAST.
Compare HADT time with HAST time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.
Time Difference
Hawaii Standard Time is 0 hours ahead of Hawaii-Aleutian Standard Time
2:00 am02:00 in HST is 2:00 am02:00 in HAST
HST to HAST call time
Best time for a conference call or a meeting is between 9am-5pm in HST which corresponds to 9am-5pm in HAST
2:00 am02:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours
2:00 am02:00 Hawaii-Aleutian Standard Time (HAST). Offset UTC -10:00 hours
2:00 am02:00 HST / 2:00 am02:00 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 |
| 00:00 | 00:00 |
| 01:00 | 01:00 |
| 02:00 | 02:00 |
| 03:00 | 03:00 |
| 04:00 | 04:00 |
| 05:00 | 05:00 |
| 06:00 | 06:00 |
| 07:00 | 07:00 |
| 08:00 | 08:00 |
| 09:00 | 09:00 |
| 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-Aleutian Daylight Time
Offset: HADT is 9 hours behind Greenwich Mean Time (GMT) and is used in North America
Daylight Saving: Hawaii-Aleutian Daylight Time (HADT) is a daylight saving/summer time zone, but some places set clocks back one hour during winter and observe Hawaii-Aleutian Standard Time (HAST).
End: Hawaii-Aleutian Daylight Time (HADT) ended on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am local standard time instead. Daylight saving ends annually on the first Sunday of November
Start: Hawaii-Aleutian Daylight Time (HADT) starts on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am. Daylight saving starts annually on the second Sunday of March
HADT representations, usage and related time zones
- -09 - basic short
- -0900 - basic
- -09:00 - extended
- -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.
- Victor - Military abbreviation for HADT
- V - short form of 'Victor'
- 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 America
Daylight Saving: This is a standard time zone. During summer, some places set clocks forward one hour for daylight saving time and observe Hawaii-Aleutian Daylight Time (HADT).
Start: Hawaii-Aleutian Standard Time (HAST) started on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually on the first Sunday of November.
End: Hawaii-Aleutian Standard Time (HAST) ends on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am local daylight time instead. Standard time ends annually on the second Sunday of March.
HAST representations, usage and related time zones
- -10 - basic short
- -1000 - basic
- -10:00 - extended
- -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.
- Whiskey - Military abbreviation for HAST
- W - short form of 'Whiskey'
- HAST - Hawaii-Aleutian Standard Time
- CKT - Cook Island Time
- HST - Hawaii Standard Time
- TAHT - Tahiti Time
- W - Whiskey Time Zone