Whether you're planning a call to family, scheduling a meeting across continents, or working out what time you'll land, getting the time zone right matters. The patterns aren't hard once you know them — and one trap, daylight saving, catches almost everyone.
Ahead or behind?
Time zones are measured as offsets from UTC. Places east of you are generally ahead (later in the day), and places west are behind (earlier). So when it's afternoon in Europe, it's still morning in the Americas and already evening or the next day in Asia and Australia. Crossing the International Date Line in the Pacific can even shift you a whole calendar day, which catches out many first-time long-haul travellers.
The common scenarios
- Calling home while away — work out the difference once and note a couple of "good windows" that are daytime in both places, usually your morning and their evening or vice versa.
- Remote work across zones — find the overlap in working hours; even a 2–3 hour window of shared daytime is enough for meetings, with the rest handled asynchronously.
- Working out your arrival time — flight arrival times are shown in the destination's local time, so convert your departure plus flight duration into local time to plan transport and gauge jet lag.
Convert a time
Estimate yours below — pick your city and time, then the destination, and it shows the difference and whether it lands on a different day.
Convert → time between cities
Indicative only — always confirm the current offset for your specific dates, since daylight saving shifts it.
Watch out for daylight saving
The trickiest part of time zones is daylight saving time. Many countries shift their clocks by an hour for part of the year — but not all do, and they don't all switch on the same dates. That means the difference between two places can change by an hour or two depending on the season, with short windows where the gap is unusual. When scheduling something weeks ahead, double-check the offset for that actual date rather than today's.
Go deeper
Questions
How do I know if a place is ahead of or behind me?
As a general rule, places to your east are ahead (later in the day) and places to your west are behind (earlier). The converter above gives the exact difference, including any daylight saving offset.
What is the best time to call across time zones?
Find a window that's daytime for both people — often one side's morning and the other's evening. Work it out once and agree a couple of regular slots, so you avoid calling when the other person is asleep.
Why does the time difference sometimes change?
Daylight saving time. Many places move their clocks forward an hour in summer and back in winter, and they don't all do it on the same dates (or at all). So the gap between two cities can vary by an hour or two through the year — always check for the specific date you're scheduling.
What is the International Date Line?
An imaginary line in the Pacific where the calendar date changes. Crossing it westward you "lose" a day; eastward you "gain" one. This is why a flight can appear to arrive on a different date than you'd expect — factor it in when reading long-haul itineraries.
How do I schedule a meeting weeks in advance across zones?
Check the offset for the actual future date, not today's, because daylight saving may shift it. Confirm the time in both participants' local zones explicitly, and a shared calendar invite that auto-adjusts to each person's zone removes most of the risk.
Does my phone update the time automatically abroad?
Usually yes, if "set automatically" is on and you have signal or wifi — your phone picks up the local zone. It's worth double-checking on arrival, and being aware that alarms set before you travel may go off on the old zone until it updates.
Time zone offsets and daylight saving rules vary by country and change over time. This is general guidance only — always confirm the current local time and offset for your specific dates.