5time zones · westbound
New York is 5 hours behind London: shift your body clock 5 hours later.
- Time difference
- New York −5 h
- Direction
- Westbound
- Body clock shift
- 5 h later
- Flight
- 10:00 → 12:23 local · ~7h 23m
Rough adaptation window: About 2 days after you land with the head start — about 4 days without it. See the plan
Your plan: 5 time zones west, body clock 5 h later
Times are local to where you are that day: London time before you fly, New York time after you land.
| Day | Sleep | Seek bright light | Avoid bright light |
|---|---|---|---|
| 3 days before · London | 00:00–08:00 | 22:00–00:00 | 08:00–10:00 |
| 2 days before · London | 01:00–09:00 | 23:00–01:00 | 09:00–11:00 |
| 1 day before · London | 02:00–10:00 | 00:00–02:00 | 10:00–12:00 |
| Flight day · London | Depart 10:00, land around 12:23 New York time.Set your watch to New York time when you board, and sleep on the plane if it's night there. | ||
| Arrival day · New YorkBody clock 2 h ahead of local time | 23:00–07:00 | 22:00–23:00 | — |
| Day 2 · New YorkBody clock 30 min ahead of local time | 23:00–07:00 | — | — |
| Day 3 · New York | 23:00–07:00 | Your body clock should be on local time — keep your usual routine. | |
A dash means the window falls while you're asleep or in the air. Bright light means daylight outdoors where you can get it; avoiding it means staying indoors, dimming the lights or wearing sunglasses.
- Daylight outdoors is many times brighter than indoor light, even on a cloudy day — it's what moves the body clock most.
- If you nap, keep it to about 20 minutes, so it doesn't eat into the night's sleep.
General information drawn from published sleep research, not medical advice. A plan like this can help your body clock adjust faster; nothing prevents jet lag outright. If you have a sleep disorder, are pregnant or take medication, talk to a doctor first. Some people use melatonin — ask a doctor or pharmacist before you try it.
Taking this trip? Add the route to Orbit. It logs the distance, the hours and the time zones crossed, on a globe you keep.
Add LHR → JFK to OrbitA few published rules, applied to your trip
Your body clock has a low point — the bottom of your core body temperature — about 3 hours before you usually wake. Bright light in the hours after it moves the clock earlier; light in the hours before it moves the clock later. That's the model behind Eastman and Burgess's “How to travel the world without jet lag” , and the light windows in the table are placed around it.
Before you fly, the plan moves your sleep 1 hour a day for up to 3 days, as the CDC Yellow Book suggests. After landing it assumes the clock catches up about 1 hour a day going east and 1.5 hours a day going west, and you sleep on local time from the first night.
Flying 8 or more hours east, the body clock tends to adjust the long way round, so the plan delays it instead. Under 3 hours there's nothing to plan — the American Academy of Sleep Medicine puts the start of jet lag at two time zones — and for trips of 2 nights or fewer it suggests staying on home time.
The time difference comes from the airport time difference calculator, daylight saving included, and the flying time from the distance calculator's estimate. Flying from somewhere new? Find the airports nearby.
Questions about jet lag
It finds the time difference between the two airports on your departure date, daylight saving included, then applies a few published rules. Your body clock's low point is about 3 hours before your usual wake time; light in the hours after it moves the clock earlier, light in the hours before it moves it later. You shift your sleep an hour a day for up to 3 days before leaving, and after landing the clock catches up about an hour a day going east and an hour and a half going west. Everything runs in your browser.
Taking this trip? Add the route to Orbit.
Orbit logs each flight — the airports, the distance, the hours and the time zones crossed — on a globe you can spin. Offline, free to start.