City comparison · time difference and converter
Seoul and Osaka share the same wall clock right now right now. Osaka sits in Japan on Tokyo; Seoul sits in South Korea on Seoul. They are roughly 829 km apart (515 mi), a flight of about 1h 59m. Osaka's metro holds around 19.1 million people; Seoul's around 25.7 million.
Slot 1
09:00 / 09:00
Osaka / Seoul
Both inside business hoursSlot 2
10:00 / 10:00
Osaka / Seoul
Both inside business hoursSlot 3
11:00 / 11:00
Osaka / Seoul
Both inside business hoursEach row is one hour in Osaka. 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.
Local Election Day
Seoul, South Korea · 지방 선거일
Wed, Jun 3
Memorial Day
Seoul, South Korea · 현충일
Sat, Jun 6
Great-circle distance
829 km
(515 mi)
Approximate flight
1h 59m
850 km/h cruise + 1h taxi/climb/descent
Jet lag
0h
Roughly 1 day to adjust per timezone crossed
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 →The difference between Osaka and Seoul is not really a number, it's a daily rhythm. Seoul and Osaka share the same wall clock right now on the clock today, but the lived version is that the two cities share the same clock, so any meeting time that works for one works for the other. That gap, more than the raw offset, is what teams have to design around.
In Osaka, the working day picks up earliest in the financial districts — Osaka's downtown core wakes early and breaks for lunch at the usual hour. The mood in Seoul is its own story: Seoul settles into the evening at the usual hour, with the local commuter pattern setting the pace. 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. Japan either observes DST or holds a fixed offset year-round; South Korea either follows its region's DST pattern or stays put all year. When the two changes are weeks apart, the offset between Osaka and Seoul 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 1h 59m 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 0-hour gap costs about 0 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.