New York to Paris Jet Lag

Crossing six time zones east, New York to Paris is one of the more demanding long-haul routes to adjust for. You leave New York around 16:30 and land in Paris around 05:55 with the morning ahead - the harder position for an eastbound traveler. This trip is harder to adjust for because it runs against the direction the human clock naturally tends to drift.

What is happening to your clock

Your body temperature has a lowest point each night: the temperature minimum, where alertness is at its worst. For a New York sleeper with a 22:30 bedtime, that falls around 3:30 in the morning. Getting to Paris time means sliding it six hours earlier, to 3:30 in the Paris night. It moves slowly - about an hour per day - and light is what drives it: evening light delays the clock, morning light advances it. Going east, the strategy is to get light in the morning and avoid it in the late evening. An evening dose of melatonin helps too, nudging the clock earlier alongside the morning light.

The chart below maps the full plan in one view: when to shift before departure, how to handle light on travel day, and where the temperature minimum lands each day as it moves from New York time toward Paris.

Read the top scale as New York time and the bottom as Paris time. The dark sleep bands start in the New York night and edge earlier each day, until they settle into the Paris night. The amber marker - your temperature minimum - drifts along with them.

Start shifting your clock in New York

The two days before departure can be leveraged to nudge your clock toward Paris before you leave, so you land part of the way there rather than facing the full six-hour gap at once. Going east, a few prepared mornings at home are worth more than anything you can do on the plane.

Each day, pull bedtime earlier, from 22:30 toward half past eight, and meet the morning with bright light as soon as you wake - outdoors if you can. Coming just after your temperature minimum, it drags the clock earlier. Keep the late evening dim so light can’t push it back the other way. A dose of melatonin, if you are taking it, in the evening a few hours before your new earlier bedtime, adds a second gentle pull in the same direction.

Over two days, the temperature minimum drifts roughly an hour per day. You can follow it on the chart: the amber marker shifts across the pre-flight rows, and the gap to Paris narrows before the flight even appears.

Landing in the morning

On flight day, what matters is to keep the clock moving the same direction. Flight AF1 leaves JFK around 16:30 and touches down in Paris near 05:55, with the morning ahead.

The eastbound red-eye has a trap built into it: it is tempting to step straight into the early light, but at that hour your temperature minimum is around the same time, and bright light too soon can still drag the clock the wrong way. Keep the first hour dim, then move into the light to make sure you’ll keep advancing your clock. Sleep on the plane where you can, because you land with a full day to get through, and zap the light at landing with sunglasses.

The first few days

Each following day repeats the same pair: morning light to keep shifting the clock, a dim late evening to stop late light from pulling it back. The temperature minimum drifts the last hour or two and settles.

Your bedtime eases back toward a normal 22:30, and an evening dose of melatonin continues for the first nights in Paris. Keep coffee to the morning and early afternoon - caffeine taken later finds its way into your sleep. Most people are on Paris time after about three nights on the ground, seven in total counting the run-up in New York, so stick with the plan through that third night even if you feel mostly fine sooner.

Why east is the harder direction

The human clock runs slightly long - around 24.2 hours on average - and drifts later on its own. An eastbound trip asks for the opposite, so the body resists and the clock moves only about an hour a day. That is why it leans on every cue at once: morning light, a dim evening, and an evening dose of melatonin all pulling the same way. Westbound trips ask for exactly what the clock already tends to do, which is why they are the easier ones.

Make it your own

This guide assumes one specific flight and a 22:30-to-06:30 sleeper. A different departure time or sleep pattern shifts every light, sleep and melatonin window with it, because these cues only move the clock when they fall at the right moment relative to your temperature minimum. The Jetlag Coach app calculates the exact windows for your actual flight and sleep schedule.