Every spring and every autumn, the gap between Los Angeles and Tokyo shifts by a full hour. Japan never touches its clocks. Pacific Time does, twice a year. That is the only moving part in this conversion, and missing it means a missed meeting or a 4 a.m. phone call.
From early November to mid-March, Pacific Standard Time runs 17 hours behind Japan Standard Time. From mid-March to early November, Pacific Daylight Time cuts that to 16 hours. Japan Standard Time stays fixed at UTC+9 all year.
What is the time difference between PST and JST?
During Pacific Standard Time, add 17 hours to get JST. During Pacific Daylight Time, add 16 hours.
On 15 January 2026, Tokyo was 17 hours ahead of Los Angeles. On 15 July 2026, Tokyo was 16 hours ahead of Los Angeles. The dates tell the story: winter widens the gap, summer narrows it.
Why does the PST to JST offset change twice a year?
Japan has no daylight saving time. Japan Standard Time (UTC+9) does not move. Only the Pacific side moves.
When clocks spring forward in the US (second Sunday of March), the gap shrinks by one hour. When they fall back (first Sunday of November), the gap widens by one hour. European DST changes do not affect the Pacific-to-Japan offset at all.
How many hours ahead is JST during PDT?
Sixteen hours. If it is 09:00 in San Francisco on a July morning, it is 01:00 the next day in Tokyo. This offset holds from the second Sunday of March through the first Sunday of November.
How many hours ahead is JST during PST?
Seventeen hours. If it is 09:00 in Los Angeles on a January morning, it is 02:00 the next day in Tokyo. This offset holds from the first Sunday of November through the second Sunday of March.
When does the PST to JST gap change in 2026 and 2027?
Pacific Time shifts on these dates:
- Sunday 8 March 2026: clocks go forward. PDT begins. Gap becomes 16 hours.
- Sunday 1 November 2026: clocks go back. PST resumes. Gap becomes 17 hours.
- Sunday 14 March 2027: clocks go forward. PDT begins. Gap becomes 16 hours.
- Sunday 7 November 2027: clocks go back. PST resumes. Gap becomes 17 hours.
Japan does nothing on any of these dates.
Common PST to JST conversions
| Pacific Time (local) | JST in winter (PST) | JST in summer (PDT) |
|---|---|---|
| 06:00 | 23:00 same day | 22:00 same day |
| 09:00 | 02:00 next day | 01:00 next day |
| 12:00 | 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 |
Add 17 hours in winter or 16 hours in summer. If the result crosses midnight, the day advances.
Is it the same calendar day in Japan when it is morning in California?
Rarely. From roughly 07:00 to 16:00 Pacific Time, JST has already rolled into the next calendar day. Japan shares the same date only from about 17:00 to 06:59 Pacific Time.
Does Japan ever use daylight saving time?
No. Japan has debated DST several times, most seriously after the 2011 energy crisis, but has never adopted it. The country remains on UTC+9 year-round. Any future change would require legislation; check the Japanese government's official announcements for current status.
Can I use a fixed offset for PST to JST?
No. A 16.5-hour average is wrong half the year. The offset is exactly 17 hours during PST and exactly 16 hours during PDT. There is no fractional offset.
Do European clock changes affect the Pacific-to-Japan difference?
No. The offset depends entirely on whether Pacific Time is in PST or PDT. British Summer Time and Central European Summer Time are irrelevant to this conversion.
Which cities use Pacific Time?
Los Angeles (population 3,820,914), Tijuana (1,922,523), San Diego (1,404,452), Mexicali (1,032,686), San Jose (997,368), San Francisco (827,526), Seattle (780,995), Vancouver (662,248), Portland (652,503), Las Vegas (641,903), Surrey (568,322), Fresno (542,107), Sacramento (524,943), Long Beach (474,140), and Ensenada (443,807).
All observe the same DST schedule. Tijuana, Mexicali, and Ensenada follow US DST despite Mexico's general abolition of daylight saving in 2022.