Flight Time
1,258 km
Distance
1,258 km
782 mi
Flight Time
1h 49m to 2h 18m
🇯🇵 Tokyo → 🇰🇷 Seoul
NRT to ICN — Complete travel planning guide
Time Difference
23:30
Tokyo
0h
difference
23:30
Seoul
Jet Lag Severity
MildModerateSevere
mild
Severity
0
Zones crossed
1d
To adjust
Adjustment Timeline
Day 1
06:00 – 23:00
Evidence-based recommendations
Each recommendation below is graded by how strongly published research supports it, with the source it comes from. Optimal timing depends on your travel direction, the number of time zones crossed and your own circadian phase, so treat the schedule as a starting point.
Protect sleep around the flight
ModerateArriving without a large sleep debt makes the first days easier, even when few time zones are involved.
CDC Yellow Book 2026Live on destination time on arrival
ModerateSleeping, eating and being active on local time gives your body consistent cues about the new day.
CDC Yellow Book 2026Drink water, go easy on alcohol
Practical adviceHydration and moderate alcohol help with travel fatigue, though they do not shift your body clock.
CDC Yellow Book 2026
How we grade evidence
- Strong
- Consistently supported by controlled circadian research and current public-health guidance.
- Moderate
- Supported by research, but effect size and best timing vary between individuals and studies.
- Practical advice
- Sensible travel habits with limited direct evidence for shifting the body clock.
This is general travel information, not medical advice. Talk to a clinician before using melatonin or sleep medication, especially if you are pregnant, take other medication or have a sleep disorder.
Flying the other way?Seoul → Tokyo
Flying from Tokyo to Seoul
The flight from Tokyo (NRT) to Seoul (ICN) covers approximately 1,258 kilometers (782 miles) based on the great-circle distance between both airports. This is the shortest theoretical path over Earth's surface, though actual flight paths may be slightly longer due to air traffic routing, weather avoidance, and airspace restrictions.
The estimated non-stop flight time is 1h 49m to 2h 18m, assuming a modern jet cruising at approximately 850 km/h. This gate-to-gate estimate includes time for taxi, takeoff, climb, cruise, descent, and landing. Actual duration varies based on wind conditions — particularly the jet stream — aircraft type, and airport congestion at both ends.
Seoul is in the same time zone as Tokyo. Travelers crossing 0 time zones within the same time zone can expect mild jet lag, with full circadian adjustment typically taking about 1 day.
With minimal or no time zone change on this route, jet lag shouldn't be a significant concern. Focus on staying hydrated and rested during the flight.
Route facts: NRT → ICN
| Detail | NRT | ICN |
|---|---|---|
| Airport | Narita International (NRT) | Incheon International (ICN) |
| City & country | 🇯🇵 Tokyo, Japan | 🇰🇷 Seoul, South Korea |
| Coordinates | 35.76°N, 140.39°E | 37.46°N, 126.44°E |
| IANA time zone | Asia/Tokyo | Asia/Seoul |
| Current UTC offset | UTC+9 | UTC+9 |
| Local time now | 23:30 | 23:30 |
Flight path, direction and distance
Leaving Tokyo, the great-circle track to Seoul starts on an initial bearing of about 283° (WNW). The route measures 1,258 km, or 679 nautical miles — the unit airlines actually plan with. Because the shortest path on a sphere is a curve rather than a straight line on a flat map, the real track may look like it bends far north or south of the direct line you would draw on a wall map.
At this length the sector is a short-haul flight of around 2h 3m, normally flown by narrow-body aircraft with a single cabin service and no crew rest.
This is an international sector, so allow additional time for immigration and customs on arrival — typically 30 to 60 minutes on top of the block time before you are landside.
Departure and arrival times: Tokyo to Seoul
Using an estimated block time of 2h 3m and the current offset between the two cities, this table shows what local time you would land in Seoul for common departure times from Tokyo. Use it to pick a departure that puts your arrival in daylight, which makes the first day of adjustment much easier.
| Departure (Tokyo) | Arrival (Seoul) | Arrival day |
|---|---|---|
| 06:00 | 08:04 | Same day |
| 10:00 | 12:04 | Same day |
| 14:00 | 16:04 | Same day |
| 18:00 | 20:04 | Same day |
| 22:00 | 00:04 | Next day |
Times are estimates based on great-circle distance and current time zone offsets, not airline schedules. Always confirm with your carrier.
Daylight: Tokyo vs Seoul
Daylight length is what actually resets your body clock, and it differs between Tokyo and Seoul through the year. In Seoul the day runs from about 9.6 h to 14.8 h across the four dates below, which changes how much morning or evening light you can realistically get after landing.
| Date | Sunrise Tokyo | Sunrise Seoul | Sunset Seoul | Day length vs origin |
|---|---|---|---|---|
| March equinox · March 20 | 05:44 | 06:40 | 18:45 | ±0 |
| June solstice · June 21 | 04:22 | 05:13 | 19:58 | +0.2 h |
| September equinox · September 22 | 05:25 | 06:21 | 18:33 | ±0 |
| December solstice · December 21 | 06:44 | 07:45 | 17:19 | −0.2 h |
Daylight saving on this route in 2026
Tokyo keeps the same offset all year (Asia/Tokyo), with no daylight saving changes.
Seoul keeps the same offset all year (Asia/Seoul), with no daylight saving changes.
The gap between Tokyo and Seoul stays at 0 h all year, so your travel date does not change the time difference.