I land at 6am and I have no idea what that will feel like

The itinerary says 06:15. That is a fact about the destination, and it tells you nothing useful about what you will be capable of when you get there.

The number you actually want is what 06:15 there is in the clock you are currently living on.

Do the conversion in the other direction

Everyone converts the destination into local terms. For arrival planning, convert it back into your terms.

New York to London, landing 06:15 GMT, having left the previous evening: that is about 01:15 by your body, in the deepest part of your night, after perhaps four broken hours of sleep in a seat.

You are not arriving in the morning. You are arriving in the middle of your night and the sun happens to be up.

That single reframing prevents most bad red-eye planning, which is people scheduling a 10am meeting because 10am sounds civilised.

What the first day is actually for

Do not schedule anything that matters before mid-afternoon. You will be functional, in the sense of being able to walk and talk. You will not be functional in the sense of negotiating, presenting or making decisions you have to live with.

Do not go to bed on arrival. This is the single most common mistake and it extends the adjustment by days. If you must sleep, twenty minutes.

Get outside. Eastward travel needs morning light to advance your clock, and you have landed straight into it. A walk on the first morning is the most effective thing available and it costs nothing. See how to avoid jet lag.

Eat on local time, even without appetite. Meal timing is a secondary synchroniser and it helps.

Direction matters more than distance

An eastward red-eye is the hard version, because you must advance your body clock against its natural drift.

Westward red-eyes — less common, but they exist on Pacific routes — are easier, and the arrival is more likely to feel like a very long day than a wrecked one.

The two things to check before booking

What the landing hour is in your own body's time. If it is 02:00–05:00 yours, treat the first day as a write-off in your planning rather than discovering it on the day.

Whether the flight crosses a clock change. If it does, the printed duration and the arithmetic will not agree, and ground transport at the arrival end may be retimed. See flights across a clock change.

And if you cannot avoid the early meeting

Some trips are one day long and the meeting is the reason you flew.

For those, the honest strategy is to stay on home time entirely — do not adjust, schedule the meeting in whatever destination hour corresponds to your own daytime if you have any say, and fly home before the mismatch compounds. Adjusting and re-adjusting inside 48 hours costs more than being out of step for one day.

Related: Coming back is worse than going out · How long does jet lag last?

Figures on this page are computed from the IANA time zone database. Last generated 2026-08-18.