About the Flight Time Calculator
This flight time calculator solves the two questions that time zones make confusing. In duration mode, enter the departure and arrival times exactly as printed on your ticket — each in its own local time — and it tells you how long you will actually be in the air. In arrival mode, enter your departure time and the scheduled flight length, and it tells you the local date and time you will land at your destination.
It is useful for checking an itinerary, working out whether a connection is realistic, planning a pickup at the airport, or understanding why an eastbound overnight flight seems to “take” 14 hours on the clock but lasts only 7. Both the departure and arrival offsets are looked up for the actual date from the IANA time zone database, so daylight saving time is handled automatically — including the weeks when Europe and North America change clocks on different dates.
Airline schedules are block times (gate to gate), which include taxiing. The calculator reports the elapsed time between the two local times you enter, so it matches the schedule rather than the time spent airborne.
How to use the flight time calculator
- 1Choose whether you want the flight duration or the local arrival time.
- 2Pick the departure time zone and enter the local departure date and time.
- 3Pick the arrival time zone.
- 4For duration, enter the local arrival date and time from your ticket.
- 5For arrival time, enter the scheduled flight length in hours and minutes.
- 6Read the answer, the time difference and the arrival time on your home clock.
Formula and method
Local times cannot be subtracted directly when a flight crosses time zones, so both are first converted to Coordinated Universal Time (UTC) by subtracting each airport’s UTC offset on that date. The difference between the two UTC instants is the true elapsed time. For example, 19:00 in New York (UTC−4) is 23:00 UTC, and 07:05 the next morning in London (UTC+1) is 06:05 UTC, a duration of 7 h 05 min.
In arrival mode the process is reversed: the departure is converted to UTC, the flight length is added, and the result is converted into the destination’s local time. Offsets come from the IANA time zone database for the specific instant, so daylight saving time is applied only when it is in force.
- UTC offset
- Hours a time zone is ahead (+) or behind (−) UTC on that date
- Duration
- Elapsed gate-to-gate time
Worked examples
New York to London overnight flight
Departing New York at 7:00 PM EDT (UTC−4) is 23:00 UTC; landing in London at 7:05 AM BST (UTC+1) is 06:05 UTC. The flight lasts 7 h 5 min, even though the clocks show a 12-hour jump because London is 5 hours ahead.
Los Angeles to Tokyo, 11 h 30 min flight
Leaving LA at 11:00 AM PDT (18:00 UTC) and flying 11 h 30 min lands at 05:30 UTC the next day. Tokyo is UTC+9, so local arrival is 2:30 PM on Friday 16 October.
Sydney to Los Angeles across the date line
Departing Sydney at 9:30 PM AEDT (UTC+11) is 10:30 UTC; arriving in LA at 6:00 PM PDT (UTC−7) on the same calendar date is 01:00 UTC the next day. The flight is 14 h 30 min, and you land earlier on the clock than you left.
Frequently asked questions
How do I calculate flight time with time zones?+
Convert both the departure and arrival times to UTC by subtracting each city’s UTC offset, then subtract. The calculator does this automatically using the correct offsets for your travel date, including daylight saving time.
Why does my eastbound flight seem so long?+
Flying east you move into time zones that are ahead of you, so the clock jumps forward during the flight. A 7-hour New York–London flight leaving at 7 PM lands at 7 AM, which looks like 12 hours on the clock.
How can I land before I took off?+
When you cross the International Date Line flying east, for example from Asia or Australia to the Americas, the local date goes back by a day. A long flight can therefore arrive at an earlier local date and time than it departed.
Is the flight time on my ticket the time in the air?+
Airline schedules show block time — from pushing back at the gate to arriving at the gate — which includes taxiing and sometimes a buffer for delays. Time actually in the air is usually 10–30 minutes shorter.
Does this handle daylight saving time?+
Yes. Offsets are looked up for the exact date and time of departure and arrival, so it correctly handles periods when one country has changed its clocks and the other has not yet.