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Tokyo vs Seoul Time Difference
Tokyo and Seoul both keep a fixed UTC+9 year-round with no daylight saving — the two cities are always exactly in sync.
Tokyo
Asia/Tokyo
Seoul
Asia/Seoul
Calculating the live gap…
Neighbors on the exact same clock
Tokyo and Seoul keep the same time year-round, both fixed at UTC+9 with no seasonal adjustment. A meeting scheduled for any hour in one city needs no conversion at all for the other — a convenience that isn't universal even among close East Asian neighbors, since China, for instance, sits a full hour behind both.
A shared offset with very different backstories
Tokyo's UTC+9 dates back to the 1880s and has barely wavered since (aside from a brief 1948-1951 daylight saving experiment). Seoul's path to the same offset was considerably bumpier: Korea adopted UTC+9 in 1912 under Japanese colonial administration, switched to UTC+8:30 in 1954 under President Syngman Rhee to better reflect Korea's own longitude, and then reverted to UTC+9 in 1961 following a change in government, largely to simplify coordination with international shipping and the US military presence. The two cities have landed on the same number by very different roads.
An easy pairing for two major economies
Japan and South Korea are deeply intertwined trade and technology partners, and the identical time zone removes one layer of friction that most international business relationships have to plan around — teams in Tokyo and Seoul can simply share a normal working day.
Best time to call, hour by hour
The table below runs through a full Tokyo day and shows the matching Seoul time for each hour. Since the two cities never differ, every standard business hour overlaps.
| Tokyo time | Seoul time | Both in business hours? |
|---|---|---|
| Calculating… | ||
Every row from 9:00 a.m. to 5:00 p.m. is highlighted — Tokyo and Seoul share a full working-day overlap.
How we calculate this page: both live clocks, the current gap, the DST transition dates, and the hour-by-hour overlap table are all computed directly from the IANA Asia/Tokyo and Asia/Seoul time zone data via your browser on every page load — nothing here is a fixed, hard-coded figure.
Frequently asked questions
What is the time difference between Tokyo and Seoul?
None. Both cities keep a fixed UTC+9 offset year-round with no daylight saving time, so they always show the exact same time.
Have Tokyo and Seoul always shared the same time zone?
Tokyo has held UTC+9 since the 1880s. Seoul's history is more complicated — Korea used UTC+9 under Japanese colonial rule starting in 1912, briefly switched to UTC+8:30 in 1954 to better match its true longitude, then reverted to UTC+9 in 1961, which is the offset it has kept since.
Is there a best time to call between Tokyo and Seoul?
Any standard business hour works — the two cities share a full 9:00-to-18:00 overlap every working day.
Why are Tokyo and Seoul closely linked economically?
Japan and South Korea are two of Asia's largest economies with deep trade, technology, and manufacturing ties, and their shared time zone removes any scheduling friction from that relationship — a rarity given how much East Asian business otherwise has to route around time-zone gaps with Europe and North America.
Does either Tokyo or Seoul observe daylight saving time today?
No. Neither Japan nor South Korea currently observes daylight saving time; both keep a fixed UTC+9 year-round.
How do I convert Tokyo time to Seoul time?
No conversion needed — simply use the same clock reading for both cities. For any other city, use the time zone converter on WatchTime Online.
Need a different pairing? Try the meeting planner or see all cities on the world clock.