Travel / Sleep
Jet Lag Planner
A day-by-day plan for your trip: when to go to bed in the days before you fly, and when to seek or avoid bright light after you land, from your home and destination time zones.
Jet Lag Planner: The planner works out the time difference on your travel date, daylight saving included, and the shorter way round the clock for your body. Following the CDC's travel health advice, it moves your sleep one hour a day towards the destination's time for up to three days before you leave, earlier for eastward flights and later for westward ones. After landing, light in the morning helps after flying east, and in the late afternoon and evening after flying west; the body clock catches up about an hour a day going east and an hour and a half going west. Runs 100% locally in your browser with zero server file uploads.
- Category
- Time & calendar tools
- Runs
- In your browser
- Cost
- Free · no sign-up
- Availability
- Ready to use
Runs entirely in your browser
Light is the strongest signal
The body clock resets mainly from light reaching the eyes. Morning light moves it earlier and evening light moves it later, which is why the timing of daylight after landing matters more than when you eat or nap. Outdoor light, even on a cloudy day, is far brighter than indoor lighting.
To see what time it will be at home and at your destination during the trip, use the time zone converter.
On the plane and after
Drink water, go easy on alcohol and caffeine, and keep naps after arrival short, under about 30 minutes, so you are tired at the new bedtime. To plan a full night around sleep cycles, use the sleep calculator.
How to use it
- Choose where you fly from and to, and the date of the flight.
- Enter your usual bedtime and wake time, and how many days you can prepare.
- Follow the plan: sleep a little earlier or later each day before the flight, and get light at the times shown after you land.
Privacy & limitations
Your plan is worked out in your browser; nothing is sent anywhere.
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Frequently asked questions
Why is flying east harder?
The body clock runs slightly longer than 24 hours, so it finds it easier to go to bed later than earlier. After an eastward flight you have to fall asleep before your body is ready.
Should I take melatonin?
Melatonin can help some travellers fall asleep at the new bedtime, but timing and dose matter and it is not suitable for everyone. Ask a doctor or pharmacist first.
What if my trip is only a day or two?
For short trips, many travellers keep to home time where they can, instead of adjusting and adjusting back.
Free tool · runs in your browser · no account required