Time & Date
Time Zone Converter
Convert times across time zones instantly. Add multiple cities and see them side by side.
Guide
How to use the Time Zone Converter
The Time Zone Converter helps you make a quick estimate, compare scenarios, and understand the numbers behind the result. It is designed for fast planning, with enough context to make the answer useful instead of just a number.
- Choose the starting date, ending date, time, or location values that define the interval.
- Check whether the calculator is using calendar days, business days, time zones, or live countdown timing.
- Use the result breakdown to confirm the date math before copying it into a schedule or plan.
Method
How this calculator works
It converts through UTC offsets using the browser's time zone data, including daylight saving adjustments.
This calculator is useful for scheduling calls and comparing local times across cities.
Because assumptions matter, try a few values that represent optimistic, typical, and conservative cases.
Date and time results depend on calendar rules, local time zones, daylight saving changes, and the exact time selected.
Example
Worked example
2 p.m. in San Francisco in winter is 7 a.m. the next morning in Tokyo — a 17-hour gap. In summer the gap is 16 hours, because California observes daylight saving time and Japan does not. The converter applies these rules automatically for any date you pick.
FAQ
Common questions
What is the best time for a call between New York and London?
London is five hours ahead of New York for most of the year. The classic overlap is 9 a.m.–12 p.m. Eastern, which lands at 2–5 p.m. in London — late enough for New York to be at work, early enough for London not to be done.
Why does the hour difference between two cities change during the year?
Regions switch daylight saving time on different dates — the US in mid-March and early November, the EU in late March and late October — and some places (Japan, most of Arizona, India) never switch. For a few weeks a year the usual offset shifts by an hour, which is exactly the kind of mistake this converter prevents.
What information do I need for the Time Zone Converter?
You usually need source city or time zone, destination city or time zone, date, and time. You can change the inputs and recalculate as many times as needed.
How does the Time Zone Converter calculate the result?
It converts through UTC offsets using the browser's time zone data, including daylight saving adjustments.
Are the results exact?
Date and time results depend on calendar rules, local time zones, daylight saving changes, and the exact time selected.
Related
Related calculators
Sources