AEST to HST Time Converter
HST is 21 hours behind AEST. Eastern Australia is currently on AEDT (UTC+11:00), and HST is UTC-10:00.
Best Time to Call Between AEST and HST
Both zones are inside normal business hours between 9:00 AM and 2:00 PM AEST — that's 12:00 PM to 5:00 PM HST. That's a 5-hour window.
both at work AEST only HST only neither — hours along the strip are AEST.
Common Times Converted
AEST on the left, HST on the right.
AEST to HST: Full 24-Hour Conversion Table
Shaded rows are working hours; the darker shade marks the hours when both zones are at work.
| AEST | HST | Working hours |
|---|---|---|
| 12:00 AM | 3:00 AM prev day | — |
| 1:00 AM | 4:00 AM prev day | — |
| 2:00 AM | 5:00 AM prev day | — |
| 3:00 AM | 6:00 AM prev day | — |
| 4:00 AM | 7:00 AM prev day | — |
| 5:00 AM | 8:00 AM prev day | — |
| 6:00 AM | 9:00 AM prev day | HST only |
| 7:00 AM | 10:00 AM prev day | HST only |
| 8:00 AM | 11:00 AM prev day | HST only |
| 9:00 AM | 12:00 PM prev day | Both zones |
| 10:00 AM | 1:00 PM prev day | Both zones |
| 11:00 AM | 2:00 PM prev day | Both zones |
| 12:00 PM | 3:00 PM prev day | Both zones |
| 1:00 PM | 4:00 PM prev day | Both zones |
| 2:00 PM | 5:00 PM prev day | AEST only |
| 3:00 PM | 6:00 PM prev day | AEST only |
| 4:00 PM | 7:00 PM prev day | AEST only |
| 5:00 PM | 8:00 PM prev day | — |
| 6:00 PM | 9:00 PM prev day | — |
| 7:00 PM | 10:00 PM prev day | — |
| 8:00 PM | 11:00 PM prev day | — |
| 9:00 PM | 12:00 AM | — |
| 10:00 PM | 1:00 AM | — |
| 11:00 PM | 2:00 AM | — |
What AEST and HST Actually Are
AEST — Australian Eastern Standard Time
Sydney, Melbourne, Brisbane, Canberra, Hobart. Standing at UTC+10:00 as written, and the region does change its clocks, so its live offset moves by an hour twice a year. The next change is on Sunday, April 4, 2027, to AEST. Sydney and Melbourne move to AEDT (UTC+11) for the southern summer; Brisbane does not change at all.
Queensland abandoned daylight saving after a 1992 referendum, so for five months a year Brisbane and Sydney read different clocks despite sharing a zone.
HST — Hawaii Standard Time
Honolulu and the rest of Hawaii. Standing at UTC-10:00 as written, and the region does not change its clocks, so that offset holds all year. Hawaii does not observe daylight saving, so this offset holds all year.
Hawaii dropped daylight saving in 1967 and never resumed it. Being close to the equator, its daylight barely varies across the year, so there is little to gain.
What This Means in Practice
The date changes mid-working-day
For 8 of the eight hours in a normal AEST working day, the equivalent HST time falls on a different calendar date. Anything scheduled in that stretch needs the date checked as well as the time, or a Tuesday call quietly becomes a Wednesday one at the other end.
This gap is not fixed
AEST changes its clocks and HST does not, so the difference between them moves by an hour twice a year. A recurring meeting set now will drift for one side from Sunday, April 4, 2027 unless someone resets it.
Nearly opposite sides of the clock
At 21 hours apart, one side's morning is the other side's night. Handing work over at the end of a shift usually beats trying to get both parties in the same call.
Major Cities in Each Zone
Cities on AEST
Cities on HST
Frequently Asked Questions
What is the time difference between AEST and HST?
HST is 21 hours behind AEST. That is the live figure. Taken strictly as written, the gap between AEST and HST is 20 hours — the two differ because at least one of these regions is currently on daylight saving.
What is 9:00 AM AEST in HST?
9:00 AM AEST is 12:00 PM the previous day HST.
What are the best hours to schedule a call between AEST and HST?
Between 9:00 AM and 2:00 PM AEST, which is 12:00 PM to 5:00 PM HST. Both sides are inside normal business hours through that window.
Does the difference between AEST and HST change during the year?
Yes. AEST observes daylight saving and HST does not, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, April 4, 2027.
Does AEST always mean Australian Eastern Standard Time?
Sydney and Melbourne move to AEDT (UTC+11) for the southern summer; Brisbane does not change at all.
Does HST always mean Hawaii Standard Time?
Hawaii does not observe daylight saving, so this offset holds all year.