Offsets use standard UTC values and do not automatically adjust for daylight saving — double-check the actual local time if either city is currently observing DST.
Converting a time across timezones sounds like simple addition, but two things routinely make it go wrong: forgetting that the result can land on a different calendar day, and forgetting that many countries shift their clocks for daylight saving at different times of year, or don't observe it at all. This tool handles the day-rollover automatically — if adding or subtracting hours pushes the time past midnight, it flags that the result falls on the next or previous day rather than silently showing a wrong-looking time.
Each city carries a standard UTC offset — its position relative to Coordinated Universal Time, the reference point all timezones are measured against. These figures reflect standard time. Countries that observe daylight saving shift their clocks forward, typically by one hour, for part of the year, which temporarily changes the effective offset. Because DST start and end dates differ by country and even by hemisphere, this tool intentionally does not try to guess a current DST state — doing so reliably would require knowing today's date against dozens of different countries' individual DST rules, and getting it wrong is worse than being transparent that it isn't factored in.
For scheduling a call, convert your intended meeting time into the other city's local time and sanity check it isn't the middle of their night. For flights, this tool is a good starting point for planning when you'll land in local terms, but always cross-check against your actual boarding pass, which shows the airline's own calculated local arrival time already adjusted for both timezones and any DST currently in effect.
It helps to think of UTC as the fixed anchor and every city as sitting some number of hours ahead of or behind it. Cities east of the reference point (like Tokyo or Sydney) sit ahead in time; cities west (like New York or Los Angeles) sit behind. When the difference between your two chosen cities exceeds twelve hours, remember that "ahead" and "behind" can wrap around the same way a 24-hour clock does, which is exactly the scenario where manual mental math most often produces an off-by-one error that this calculator avoids.
Once you've settled the time for your destination, the Jet Lag Recovery Calculator can tell you roughly how many days it will take your body clock to adjust to that shift, and the Layover Time Calculator helps you judge connection windows once you know the local times involved.
One more nuance worth knowing: a handful of regions use timezone offsets that aren't a whole number of hours — India, Iran and parts of Australia among them — which is why this tool supports half-hour offsets rather than assuming every timezone sits on a neat hourly boundary. A small number of places go further still and use a 45-minute offset, a reminder that timezone boundaries follow political and historical decisions as much as geography, and are worth double-checking individually rather than assumed from a country's general region.
No. It uses fixed standard-time UTC offsets. If either city is currently observing daylight saving, add or subtract an hour manually based on that country's current DST status.
Because the time difference pushed the result past midnight into the next calendar day — a common and easy-to-miss effect when converting into a city many hours ahead of your own.
Yes, the calculation works the same way regardless of direction — it simply adds the difference between the two offsets, which is negative when converting into a city further behind UTC.
A set of major global cities commonly used as flight and business hubs. If your exact city isn't listed, use the nearest major city in the same country, since most countries use only one or two timezones.