Updating current time…
HST
12am
3am
6am
9am
12pm
3pm
6pm
9pm
Y
UTC−12
2h behind
12am
3am
6am
9am
12pm
3pm
6pm
9pm

Quick answers

Selected conversion

2:00 am02:00 HST (UTC-10), Oct 22, 2026 = 12:00 am00:00 Y (UTC-12), Oct 22, 2026

HST is 2 hours ahead of Y.

HST and Y examples

These examples always use HST (UTC-10) and Y (UTC-12). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.

HST is 2 hours ahead of Y.

How the time difference changes

HST is 2 hours ahead of Y year-round.

Working hours of 9:00 am to 6:00 pm in HST correspond to 7:00 am to 4:00 pm in Y.Working hours of 09:00 to 18:00 in HST correspond to 07:00 to 16:00 in Y.

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

Time Difference

Hawaii Standard Time is 2 hours ahead of Yankee Time Zone.
2:00 am02:00 in HST is 12:00 am00:00 in Y

HST to Y call time
Best time for a conference call or a meeting is between 11am-6pm11:00-18:00 in HST which corresponds to 9am-4pm09:00-16:00 in Y

2:00 am02:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours
12:00 am00:00 Yankee Time Zone (Y). Offset UTC -12:00 hours

2:00 am02:00 HST / 12:00 am00:00 Y

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
HSTY
10:00pm previous day
11:00pm previous day
12:00am
1:00am
2:00am
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9:00am
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12:00pm
1:00pm
2:00pm
3:00pm
4:00pm
5:00pm
6:00pm
7:00pm
8:00pm
9:00pm
22:00 previous day
23:00 previous day
00:00
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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

Yankee Time Zone

Offset: Y is 12 hours behind Greenwich Mean Time (GMT).

Daylight Saving: Clocks in Yankee Time Zone (Y) do not change for daylight saving time, so Y stays the same throughout the year. Other time zones may set clocks forward in summer and back in winter; see upcoming clock changes worldwide.

Y representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -12 - basic short
  • -1200 - basic
  • -12:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -1200 - sign character (-) followed by a four digit time providing hours (12) and minutes (00) of the offset. Indicates an offset of twelve hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Yankee - Military abbreviation for Y
  • Y - short form of 'Yankee'