Seoul is usually 16 hours ahead of San Francisco. San Francisco observes daylight saving time and Seoul does not, so the difference shifts by an hour around the changeovers.

SeoulSan Francisco

Sunrise 5:28 AMSunset 7:50 PM(local)

Sunrise 6:05 AMSunset 8:29 PM(local)

San Francisco: daylight saving timeNow UTC-7 PDT. Next change: November 1, 2026 β€” clocks go back 1 hour.
SeoulUTC+9
San FranciscoUTC-7PDT

πŸ‡°πŸ‡· Seoul

Dialing code+82
Population10,349,312
Coordinates37.57Β°N, 126.98Β°E
Elevation38 m

πŸ‡ΊπŸ‡Έ San Francisco

Dialing code+1
Population827,526
Coordinates37.77Β°N, 122.42Β°W
Elevation16 m

Best time for a call: 09:00–10:00 in SeoulAdd to calendar

Working hours assumed 9:00–18:00.

Frequently asked questions

What is the time difference between Seoul and San Francisco?
Seoul is 16 hours ahead of San Francisco. Use the side-by-side clocks and the day/night strips above to convert any hour between them.
When is the best time to call between Seoul and San Francisco?
The best window to call is 09:00–10:00 Seoul time, when working hours overlap in both cities. Pick an hour on the strips to add it to your calendar.
Why does the time difference between Seoul and San Francisco change?
Because at least one of Seoul and San Francisco observes daylight saving time, the difference shifts by an hour when one city changes its clocks and the other has not yet (or does not).