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Time Difference Calculator
Find the hours and minutes between two clock times — each one in its own time zone, so a flight, a shift, or a call across the country all come out right.
How this works
How do I calculate the time difference between two times?
Enter a start time and an end time and this page works out the hours and minutes between them. Each side has its own time zone, so the two times can be in different places — leave both on your device's own zone for an ordinary same-place calculation.
How do I work out a flight time across time zones?
Put the departure time in the departure city's zone and the arrival time in the arrival city's zone. The answer is the real time in the air, not the difference between the two clock faces — a flight leaving Los Angeles at 10:00 AM and landing in London at 6:00 AM the next day is 13 hours, however little the clocks appear to move.
What time is it on the other coast right now?
Set the two zones and read the "put another way" line under the result: it says what the start time reads on the second clock, and how many hours apart the two are at that moment.
Does this account for daylight saving time?
Yes. Every calculation is done in real instants rather than clock faces, using today's date in each zone, so a span that crosses a daylight-saving change gets the real elapsed time. When both sides are in one zone and the clock disagrees with the real elapsed time, the page says so.
What if the end time is before the start time?
It's treated as the next such moment, so the answer is always between zero and 24 hours — 10:00 PM to 6:00 AM is 8 hours, not a negative number, and the result notes "the next day".