JST to AKST Time Converter
AKST is 17 hours behind JST. JST is UTC+9:00, and Alaska is currently on AKDT (UTC-8:00).
Best Time to Call Between JST and AKST
Both zones are inside normal business hours between 9:00 AM and 10:00 AM JST — that's 4:00 PM to 5:00 PM AKST. That's a 1-hour window.
both at work JST only AKST only neither — hours along the strip are JST.
Common Times Converted
JST on the left, AKST on the right.
JST to AKST: Full 24-Hour Conversion Table
Shaded rows are working hours; the darker shade marks the hours when both zones are at work.
| JST | AKST | Working hours |
|---|---|---|
| 12:00 AM | 7:00 AM prev day | — |
| 1:00 AM | 8:00 AM prev day | — |
| 2:00 AM | 9:00 AM prev day | AKST only |
| 3:00 AM | 10:00 AM prev day | AKST only |
| 4:00 AM | 11:00 AM prev day | AKST only |
| 5:00 AM | 12:00 PM prev day | AKST only |
| 6:00 AM | 1:00 PM prev day | AKST only |
| 7:00 AM | 2:00 PM prev day | AKST only |
| 8:00 AM | 3:00 PM prev day | AKST only |
| 9:00 AM | 4:00 PM prev day | Both zones |
| 10:00 AM | 5:00 PM prev day | JST only |
| 11:00 AM | 6:00 PM prev day | JST only |
| 12:00 PM | 7:00 PM prev day | JST only |
| 1:00 PM | 8:00 PM prev day | JST only |
| 2:00 PM | 9:00 PM prev day | JST only |
| 3:00 PM | 10:00 PM prev day | JST only |
| 4:00 PM | 11:00 PM prev day | JST only |
| 5:00 PM | 12:00 AM | — |
| 6:00 PM | 1:00 AM | — |
| 7:00 PM | 2:00 AM | — |
| 8:00 PM | 3:00 AM | — |
| 9:00 PM | 4:00 AM | — |
| 10:00 PM | 5:00 AM | — |
| 11:00 PM | 6:00 AM | — |
What JST and AKST Actually Are
JST — Japan Standard Time
Tokyo, Osaka, Yokohama, Nagoya, Sapporo. Standing at UTC+9:00 as written, and the region does not change its clocks, so that offset holds all year. Japan does not observe daylight saving, so this offset is fixed year-round.
Japan abolished daylight saving in 1952 and has resisted every attempt to reintroduce it, including a proposal around the 2020 Olympics.
AKST — Alaska Standard Time
Anchorage, Fairbanks, Juneau. Standing at UTC-9:00 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, November 1, 2026, to AKST.
Alaska compressed four time zones into one in 1983, moving most of the state onto a single clock to keep business hours aligned with the rest of the country.
What This Means in Practice
The date changes mid-working-day
For 8 of the eight hours in a normal JST working day, the equivalent AKST 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
AKST changes its clocks and JST 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, November 1, 2026 unless someone resets it.
Nearly opposite sides of the clock
At 17 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 JST
Cities on AKST
Frequently Asked Questions
What is the time difference between JST and AKST?
AKST is 17 hours behind JST. That is the live figure. Taken strictly as written, the gap between JST and AKST is 18 hours — the two differ because at least one of these regions is currently on daylight saving.
What is 9:00 AM JST in AKST?
9:00 AM JST is 4:00 PM the previous day AKST.
What are the best hours to schedule a call between JST and AKST?
Between 9:00 AM and 10:00 AM JST, which is 4:00 PM to 5:00 PM AKST. Both sides are inside normal business hours through that window.
Does the difference between JST and AKST change during the year?
Yes. AKST observes daylight saving and JST does not, so the gap shifts by an hour at least twice a year. The next clock change is on Sunday, November 1, 2026.
Does JST always mean Japan Standard Time?
Japan does not observe daylight saving, so this offset is fixed year-round.