Seoul to San Francisco Time Difference
San Francisco is 16 hours behind Seoul. When it's 11:20:10 PM in Seoul, it's 07:20:10 AM in San Francisco.
How Many Hours Behind Is San Francisco From Seoul?
San Francisco is 16 hours behind Seoul. So Seoul is 16 hours ahead of San Francisco looking the other way — the same gap, described from the other end.
In practice that means a working day in Seoul starts when it is already 5:00 PM the previous day in San Francisco. The gap is not fixed all year: it becomes 17 hours on Sunday, November 1, 2026, when San Francisco changes its clocks.
Best Time to Call Seoul and San Francisco
Standard 9-to-5 hours in Seoul and San Francisco never overlap, so someone has to take the call outside their working day. The most workable window is 7:00 AM to 2:00 PM in Seoul, which is 3:00 PM to 10:00 PM in San Francisco.
both at work Seoul only San Francisco only neither — hours shown along the strip are Seoul local time.
Convert a Specific Time
Pick any date and time in Seoul to see the exact equivalent in San Francisco.
Common Times Converted
Seoul time on the left, San Francisco time on the right.
Seoul to San Francisco: Full 24-Hour Conversion Table
Based on today, Sunday, October 11, 2026 in Seoul. Shaded rows are working hours; the darker shade marks the hours when both cities are at work.
| Seoul | San Francisco | Working hours |
|---|---|---|
| 12:00 AM | 8:00 AM prev day | — |
| 1:00 AM | 9:00 AM prev day | San Francisco only |
| 2:00 AM | 10:00 AM prev day | San Francisco only |
| 3:00 AM | 11:00 AM prev day | San Francisco only |
| 4:00 AM | 12:00 PM prev day | San Francisco only |
| 5:00 AM | 1:00 PM prev day | San Francisco only |
| 6:00 AM | 2:00 PM prev day | San Francisco only |
| 7:00 AM | 3:00 PM prev day | San Francisco only |
| 8:00 AM | 4:00 PM prev day | San Francisco only |
| 9:00 AM | 5:00 PM prev day | Seoul only |
| 10:00 AM | 6:00 PM prev day | Seoul only |
| 11:00 AM | 7:00 PM prev day | Seoul only |
| 12:00 PM | 8:00 PM prev day | Seoul only |
| 1:00 PM | 9:00 PM prev day | Seoul only |
| 2:00 PM | 10:00 PM prev day | Seoul only |
| 3:00 PM | 11:00 PM prev day | Seoul only |
| 4:00 PM | 12:00 AM | Seoul only |
| 5:00 PM | 1:00 AM | — |
| 6:00 PM | 2:00 AM | — |
| 7:00 PM | 3:00 AM | — |
| 8:00 PM | 4:00 AM | — |
| 9:00 PM | 5:00 AM | — |
| 10:00 PM | 6:00 AM | — |
| 11:00 PM | 7:00 AM | — |
Understanding the Seoul – San Francisco Time Difference
Seoul runs on Asia/Seoul, currently KST (UTC+9:00). San Francisco runs on America/Los_Angeles, currently PDT (UTC-7:00). The gap of 16 hours is simply the distance between those two offsets.
San Francisco observes Daylight Saving Time and Seoul does not, so the gap between them shifts by an hour twice a year. The next shift is on Sunday, November 1, 2026, when San Francisco adjusts its clocks and the difference becomes 17 hours. Anything scheduled across that date needs checking again.
Full clock-change dates: Daylight Saving Time in the United States.
Seoul today
San Francisco today
Frequently Asked Questions
What is the time difference between Seoul and San Francisco?
San Francisco is currently 16 hours behind Seoul. That gap becomes 17 hours on Sunday, November 1, 2026, when San Francisco changes its clocks.
How many hours behind is San Francisco from Seoul?
San Francisco is 16 hours behind Seoul. Looking at it the other way, Seoul is 16 hours ahead of San Francisco.
What time is it in San Francisco when it is 9:00 AM in Seoul?
When it is 9:00 AM in Seoul, it is 5:00 PM the previous day in San Francisco.
Is San Francisco ahead of or behind Seoul?
San Francisco is 16 hours behind Seoul. Seoul reaches each point in the day first, so San Francisco is still getting started while the Seoul working day is finishing.
What is the best time to call between Seoul and San Francisco?
Standard business hours in Seoul and San Francisco do not overlap at all, so one side has to step outside the 9-to-5. The most workable window is 7:00 AM to 2:00 PM in Seoul, which is 3:00 PM to 10:00 PM in San Francisco.
Does the time difference between Seoul and San Francisco change during the year?
Yes. San Francisco observes Daylight Saving Time and Seoul does not, so the gap between them shifts during the year. It changes to 17 hours on Sunday, November 1, 2026.
What time zones are Seoul and San Francisco in?
Seoul uses the Asia/Seoul time zone, currently KST (UTC+9:00). San Francisco uses America/Los_Angeles, currently PDT (UTC-7:00).