ClockOrbit

City comparison · time difference and converter

Gwangju vs San Francisco time difference and converter

San Francisco is 17 hours behind Gwangju right now. Gwangju sits in South Korea on Seoul; San Francisco sits in United States on Los Angeles. They are roughly 9,211 km apart (5,723 mi), a flight of about 11h 50m. Gwangju's metro holds around 1.4 million people; San Francisco's around 4.7 million.

 

Gwangju

--:--:--
UTC

 

San Francisco

--:--:--
UTC

Best meeting times today

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Slot 1

09:00 / 16:00

Gwangju / San Francisco

Both inside business hours

Slot 2

02:00 / 09:00

Gwangju / San Francisco

Partial overlap

Slot 3

03:00 / 10:00

Gwangju / San Francisco

Partial overlap

24-hour comparison heatmap

Each row is one hour in Gwangju. Green rows are inside business hours in both cities; amber means only one side is at their desk; grey rows fall outside business hours in both.

Gwangju (Seoul)
San Francisco (Los Angeles)
Status
00:00
07:00
Off-hours
01:00
08:00
Off-hours
02:00
09:00
One at work
03:00
10:00
One at work
04:00
11:00
One at work
05:00
12:00
One at work
06:00
13:00
One at work
07:00
14:00
One at work
08:00
15:00
One at work
09:00
16:00
Both at work
10:00
17:00
One at work
11:00
18:00
One at work
12:00
19:00
One at work
13:00
20:00
One at work
14:00
21:00
One at work
15:00
22:00
One at work
16:00
23:00
One at work
17:00
00:00
Off-hours
18:00
01:00
Off-hours
19:00
02:00
Off-hours
20:00
03:00
Off-hours
21:00
04:00
Off-hours
22:00
05:00
Off-hours
23:00
06:00
Off-hours

Public holidays in November 2026

Travel context

Great-circle distance

9,211 km

(5,723 mi)

Approximate flight

11h 50m

850 km/h cruise + 1h taxi/climb/descent

Jet lag

17h

Roughly 1 day to adjust per timezone crossed

Convert any specific time

The heatmap gives you the shape of the day. If you need to convert one specific hour, say a customer call or a release window, open the converter with both cities already loaded.

Open in converter →

Frequently asked questions

Working between Gwangju and San Francisco

The difference between Gwangju and San Francisco is not really a number, it's a daily rhythm. San Francisco is 17 hours behind Gwangju on the clock today, but the lived version is that Gwangju is ahead in the calendar, so by the time San Francisco comes online, half of Gwangju's day is already gone. That gap, more than the raw offset, is what teams have to design around.

In Gwangju, the working day picks up earliest in the financial districts- Gwangju's downtown core wakes early and breaks for lunch at the usual hour. The mood in San Francisco is its own story: SoMa and FiDi quiet around 18:00, with Mission bars taking the after-work crowd. If you are scheduling between the two, the heatmap above marks the rows where both patterns line up.

Daylight saving is the other thing to keep an eye on. South Korea either observes DST or holds a fixed offset year-round; United States shifts on the second Sunday of March and the first Sunday of November. When the two changes are weeks apart, the offset between Gwangju and San Francisco is one hour off the usual for that stretch, a cliff that catches recurring calendar invites unless your calendar app rebases them automatically. Pin the meeting to a city, not an offset, and the tool handles the rest.

For travellers, the 11h 50m flight is the short version of the story. The longer one is jet lag: roughly one day of adjustment per timezone crossed, which means a trip across the 17-hour gap costs about 17 groggy days on each side. Pilots and cabin crew swear by morning sunlight and an early walk; whatever your routine, the wall-clock numbers above are the source of truth for your first morning in the new city.