JST to California time conversion
California is 16 hours behind JST. After the next clock change (): California is 17 hours behind JST.
Time difference with your location
JST is 9 hours ahead of UTC. Compare with your local time →
Choose a date and time
Choose the local time in JST to convert it to California on that date.
Skipped clock-change times are unavailable; a repeated time uses its first occurrence.
24-hour conversion chart · JST → California
This table converts each hour in JST to California on 2026-10-22.
- Working hours
- Outside working hours
- Night hours
| JST | California | Shared working hours |
|---|---|---|
| 00:0012:00 AM | 08:008:00 AM -1 day | |
| 01:001:00 AM | 09:009:00 AM -1 day | |
| 02:002:00 AM | 10:0010:00 AM -1 day | |
| 03:003:00 AM | 11:0011:00 AM -1 day | |
| 04:004:00 AM | 12:0012:00 PM -1 day | |
| 05:005:00 AM | 13:001:00 PM -1 day | |
| 06:006:00 AM | 14:002:00 PM -1 day | |
| 07:007:00 AM | 15:003:00 PM -1 day | |
| 08:008:00 AM | 16:004:00 PM -1 day | ✓ |
| 09:009:00 AM | 17:005:00 PM -1 day | ✓ |
| 10:0010:00 AM | 18:006:00 PM -1 day | |
| 11:0011:00 AM | 19:007:00 PM -1 day | |
| 12:0012:00 PM | 20:008:00 PM -1 day | |
| 13:001:00 PM | 21:009:00 PM -1 day | |
| 14:002:00 PM | 22:0010:00 PM -1 day | |
| 15:003:00 PM | 23:0011:00 PM -1 day | |
| 16:004:00 PM | 00:0012:00 AM | |
| 17:005:00 PM | 01:001:00 AM | |
| 18:006:00 PM | 02:002:00 AM | |
| 19:007:00 PM | 03:003:00 AM | |
| 20:008:00 PM | 04:004:00 AM | |
| 21:009:00 PM | 05:005:00 AM | |
| 22:0010:00 PM | 06:006:00 AM | |
| 23:0011:00 PM | 07:007:00 AM |
Quick conversion examples
These examples use JST (UTC+9) and California (UTC-7); choosing a date applies the local clock changes.
Conversion formula: California = JST − 16h · JST − 17h.
| JST | California |
|---|---|
| 6:00 AM JST | = 2:00 PM California (-1 day) |
| 7:00 AM JST | = 3:00 PM California (-1 day) |
| 8:00 AM JST | = 4:00 PM California (-1 day) |
| 9:00 AM JST | = 5:00 PM California (-1 day) |
| 10:00 AM JST | = 6:00 PM California (-1 day) |
| 12:00 PM JST | = 8:00 PM California (-1 day) |
| 3:00 PM JST | = 11:00 PM California (-1 day) |
| 5:00 PM JST | = 1:00 AM California |
| 6:00 PM JST | = 2:00 AM California |
| 8:00 PM JST | = 4:00 AM California |
Overlapping meeting hours
The 08:00–18:00 working day in JST and California overlaps for 2 hours on 2026-10-22.
- Shared working hours
- 08:00–10:00 JST · 16:00–18:00 California
Clock changes on both sides, 2026–2028
JST and California have the following local clock changes in 2026–2028; all times in the table are local to that side.
| Year | JST | California |
|---|---|---|
| 2026 | No clock changes; UTC+9 all year. | · 02:00 → 03:00 · 02:00 → 01:00 |
| 2027 | No clock changes; UTC+9 all year. | · 02:00 → 03:00 · 02:00 → 01:00 |
| 2028 | No clock changes; UTC+9 all year. | · 02:00 → 03:00 · 02:00 → 01:00 |
At the start of 2026, California is 17 hours behind JST. The difference changes during the following periods.
- From 2026-03-08 19:00 JST until 2026-11-01 18:00 JST, California is 16 hours behind JST.
- From 2027-03-14 19:00 JST until 2027-11-07 18:00 JST, California is 16 hours behind JST.
- From 2028-03-12 19:00 JST until 2028-11-05 18:00 JST, California is 16 hours behind JST.
Frequently asked questions
What time is 9 AM JST in California?
9:00 AM JST = 5:00 PM California (-1 day), using UTC+9 and UTC-7. Choose a date above for the seasonal local time.
Does the time difference between JST and California change during the year?
Yes. During 2026–2028: California is 17 hours behind JST; California is 16 hours behind JST. The clock-change table gives the dates for both sides.
How do I tell whether it is day or night in California?
Read the California clock above: this guide counts 06:00–18:00 local time as daytime and the rest as nighttime, without using sunrise and sunset.
What is the best time to call between JST and California?
The shared 08:00–18:00 working window is 08:00–10:00 JST / 16:00–18:00 California, a total of 2 hours.
What is the time difference between JST and California now?
Right now, California is 16 hours behind JST. Conversion formula: California = JST − 16h · JST − 17h.