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HST to JST Time Converter

Use this HST to JST time converter to compare United States and Japan time instantly. JST is 19 hours ahead of HST, so 9:00 AM HST becomes 4:00 AM (next day) JST and 5:00 PM HST becomes 12:00 PM (next day) JST. The page is useful for business-hours overlap, international calls, remote-team handoffs, webinars, and travel planning, with daylight saving adjustments handled automatically.

HST Hawaii Standard Time
...
JST Japan Standard Time
...
Select a time to convert

HST to JST Quick Facts

Use this HST to JST converter to compare United States and Japan time, check the 19 hours gap, and confirm the right slot for calls, handoffs, and deadlines. Find the best overlap for calls and meetings.

Time Difference
Japan Standard Time is 19 hours ahead of Hawaii Standard Time
Useful when deadlines, handoffs, or calls cross workday boundaries.
Best Call Window
Normal business hours do not overlap well here, so test early-morning or late-evening compromise slots.
Common Use Cases
Useful for remote teams, customer support windows, travel planning, webinars, and same-day deadline handoffs.

How to Convert HST to JST

Converting between Hawaii Standard Time and Japan Standard Time means accounting for a 19 hours gap — here's how to do it in under 10 seconds with no sign-up.

Enter Your HST Time

Pick the date and time in Hawaii Standard Time (UTC -10) that you want to convert. Hit "Now" to load the current HST time instantly, or use "+1h" to step forward and compare.

Read the JST Result

The equivalent Japan Standard Time (UTC +9) time appears immediately. Since JST is 19 hours ahead of HST, conversions often cross midnight — look for the date-change label.

Copy or Fine-Tune

Click "Copy Time" to grab the JST result for your calendar or message. Use "+1d" to check how the conversion shifts across dates — helpful for scheduling recurring United States–Japan calls.

Why Choose Our HST to JST Converter

Align HST–JST Meetings Instantly

With 19 hours between HST and JST, business-hours overlap is limited. This tool instantly shows which hours work on both sides, so you can lock in a meeting without a chain of "does 3 PM work for you?" emails.

Spot Date-Line Shifts at a Glance

A HST evening at 9 PM is already the next morning in JST. This converter flags date changes beside the result — critical when booking flights, hitting deadlines, or scheduling across the United States–Japan corridor.

Handles DST Transitions Automatically

Daylight Saving adjustments can widen or narrow the HST–JST gap by an hour. During transition weeks many people get it wrong. This converter pulls the current UTC offsets automatically, so the result is right even on the changeover day.

Never Miss a HST-Timed Event

Product launches, sports matches, and webinars are often announced in HST. Convert the event time to JST so you know exactly when to tune in — with a 19 hours difference, a morning event in United States falls during work hours in Japan.

HST to JST Time Conversion Chart

Quick-reference conversion table covering every hour of the day at a glance.

Complete 24-Hour Conversion

Hawaii Standard Time to Japan Standard Time full day schedule

12:00 AM
HST
7:00 PM
JST
1:00 AM
HST
8:00 PM
JST
2:00 AM
HST
9:00 PM
JST
3:00 AM
HST
10:00 PM
JST
4:00 AM
HST
11:00 PM
JST
5:00 AM
HST
12:00 AM
JST
(next day)
6:00 AM
HST
1:00 AM
JST
(next day)
7:00 AM
HST
2:00 AM
JST
(next day)
8:00 AM
HST
3:00 AM
JST
(next day)
9:00 AM
HST
4:00 AM
JST
(next day)
10:00 AM
HST
5:00 AM
JST
(next day)
11:00 AM
HST
6:00 AM
JST
(next day)
12:00 PM
HST
7:00 AM
JST
(next day)
1:00 PM
HST
8:00 AM
JST
(next day)
2:00 PM
HST
9:00 AM
JST
(next day)
3:00 PM
HST
10:00 AM
JST
(next day)
4:00 PM
HST
11:00 AM
JST
(next day)
5:00 PM
HST
12:00 PM
JST
(next day)
6:00 PM
HST
1:00 PM
JST
(next day)
7:00 PM
HST
2:00 PM
JST
(next day)
8:00 PM
HST
3:00 PM
JST
(next day)
9:00 PM
HST
4:00 PM
JST
(next day)
10:00 PM
HST
5:00 PM
JST
(next day)
11:00 PM
HST
6:00 PM
JST
(next day)