Blog / How to calculate arrival time

How to figure out what time you will land

The FlightBeat team

Working out your arrival time sounds simple, until time zones get involved. A five hour flight can land at a clock time that makes no sense at first glance, sometimes even the day before you left. Here is how to do the math, and the shortcut that skips it entirely.

The basic formula

Start with your departure time in the local time of the airport you are leaving from. Add the flight time. Then add or subtract the time zone difference between the two cities. That last step is the one people forget, and it is what makes the arrival clock jump.

For example, leave New York at 8:00 PM on a 7 hour flight to London. Add 7 hours and you get 3:00 AM New York time. London is 5 hours ahead, so add 5 more and you land at 8:00 AM London time, the next morning.

Why you can land "before" you left

Fly west across many time zones and the clock can run backwards relative to your day. A flight leaving Tokyo in the evening can land in the United States on the same calendar date, at an earlier clock time than departure, because you are chasing the sun and crossing the international date line. It feels like time travel, but it is just arithmetic with time zones.

Red-eyes and next-day arrivals

Eastbound overnight flights, the classic red-eye, almost always land the next calendar day. Your body clock will still be on the departure city's time, which is why a 6:00 AM arrival can feel like the middle of the night. Knowing your arrival time in both the local zone and your home zone helps you plan sleep and beat jet lag.

Daylight saving makes it messier

Time zone differences are not fixed. When one country is on daylight saving time and the other is not, the gap between them shifts by an hour for a few weeks each spring and autumn. This is exactly the kind of detail that trips up a quick mental calculation.

The shortcut

Rather than doing this by hand, the FlightBeat calculator handles it for you. Pick your two airports and a departure time, and it shows your arrival in the destination's local zone, flags whether you land the next day, and tells you the exact time difference, with daylight saving already handled. It is accurate worldwide because every airport carries its real time zone.

Try the flight time calculator