Japan and South Korea: 9 hours of shared working time
Japan and South Korea share 9 hours of working time: 09:00–18:00 where you are, 09:00–18:00 in South Korea. Computed from each country's own working day — 09:00–18:00 and 09:00–18:00 — rather than a nine-to-five assumed for both.
Where this number comes from
Japan works 09:00–18:00 and South Korea 09:00–18:00, each on its own clock. The overlap is the intersection of those two days once both are put on the same axis .
The week on each side
Japan works Monday, Tuesday, Wednesday, Thursday, Friday. South Korea works Monday, Tuesday, Wednesday, Thursday, Friday. The weeks line up, so the only thing to get right is the hour.
What interrupts it in the next three months
A shared window is worth nothing on a day one side is closed. Japan has 敬老の日 (2026-09-21), 国民の休日 (2026-09-22), 秋分の日 (2026-09-23), スポーツの日 (2026-10-12). South Korea has 추석 (2026-09-24), 개천절 (2026-10-03), 개천절 (대체공휴일) (2026-10-05), 한글날 (2026-10-09).
Who else you can reach
Sources and last check
Times, offsets and sun positions on this page are computed live from the IANA timezone database and the NOAA solar algorithm, so they do not depend on the review dates below.
- Working hours and weekend days for 55 countries
- Source: Published national labour conventions and government working-hours guidance. Last checked, reviewed every 12 months.
Not covered:A national convention, not any given employer. Countries not listed fall back to a nine-to-five, Monday to Friday default, and pages say so rather than implying we checked. - 141 countries: representative IANA zone and whether they observe DST
- Source: Generated by scripts/build-countries.mjs from Intl.DisplayNames and the tzdata shipped with Node. Nothing typed by hand.. Last checked, reviewed every 6 months.
Not covered:13 of them span more than one zone we hold; for those, `iana` is their largest city's zone rather than the whole country's.
FAQ
What is the best time to call South Korea from Japan?
09:00–18:00 your time, which is 09:00–18:00 in South Korea. That window is where both countries are inside their own office day, so it holds for a recurring call rather than only for one that happens to land well.