Tokyo stays on UTC+9 every day of the year. Japan has not used daylight saving time since 1951. The clock in Shibuya does not move.
The clock in Los Angeles moves twice a year. That is the whole story. Pacific Time switches between UTC−8 (winter) and UTC−7 (summer), and the Japan gap compresses from 17 hours to 16.
PST to JST: 17 hours ahead in winter
When Pacific Standard Time is in effect, Japan is 17 hours ahead.
PST runs from the first Sunday in November to the second Sunday in March. In 2026, that means November 1 to March 14. At 09:00 in Los Angeles, it is 02:00 the next day in Tokyo.
Add 17 hours to any PST time. If the total passes midnight, you have crossed into the next calendar day.
PDT to JST: 16 hours ahead in summer
When Pacific Daylight Time is in effect, Japan is 16 hours ahead.
PDT runs from the second Sunday in March to the first Sunday in November. In 2026, that means March 8 to November 1. At 09:00 in San Francisco, it is 01:00 the next day in Tokyo.
Add 16 hours to any PDT time.
Quick-reference conversion table
| Pacific Time | JST (Winter, PST) | JST (Summer, PDT) |
|---|---|---|
| 00:00 (midnight) | 17:00 | 16:00 |
| 03:00 | 20:00 | 19:00 |
| 06:00 | 23:00 | 22:00 |
| 09:00 | 02:00 (next day) | 01:00 (next day) |
| 12:00 (noon) | 05:00 (next day) | 04:00 (next day) |
| 15:00 | 08:00 (next day) | 07:00 (next day) |
| 18:00 | 11:00 (next day) | 10:00 (next day) |
| 21:00 | 14:00 (next day) | 13:00 (next day) |
Why do I lose a day flying from LA to Tokyo?
A flight that departs Los Angeles at 11:00 on a Tuesday lands in Tokyo around 15:00 on Wednesday. You lose a calendar day crossing the International Date Line westbound.
Returning, you gain it back. A Tokyo departure at 17:00 on a Thursday reaches Los Angeles at roughly 10:00 the same Thursday. You live Thursday twice.
The date line sits between the two cities. Pacific Time is among the last zones to end a calendar day; Japan Standard Time is among the first to start the next one. That is why Tokyo is always a day ahead when it is afternoon or evening on the West Coast. Only the very early Pacific morning (00:00 to 02:00) shares the same calendar date with Tokyo.
What is the real window for a call between Tokyo and the West Coast?
Narrow. Tokyo office hours (09:00 to 17:00 JST) map to 17:00 through 01:00 Pacific Time in winter and 18:00 through 02:00 in summer.
The only practical same-day window is 17:00 to 18:00 Pacific in winter, or 18:00 to 19:00 Pacific in summer. That is the start of Tokyo’s next business day.
For an early Tokyo meeting at 08:00 JST, the Pacific caller dials in the previous day at 15:00 (PST) or 16:00 (PDT).
| Tokyo time | Pacific Time (PST, winter) | Pacific Time (PDT, summer) |
|---|---|---|
| 08:00 JST | 15:00 (previous day) | 16:00 (previous day) |
| 09:00 JST | 16:00 (previous day) | 17:00 (previous day) |
| 10:00 JST | 17:00 (previous day) | 18:00 (previous day) |
| 17:00 JST | 00:00 (midnight) | 01:00 |