Timezone Converter
NewConvert date and time between timezones online for free. See the equivalent local time in multiple cities at once, with UTC offsets and day differences. No signup, runs entirely in your browser.
About this tool
A timezone converter shows what a specific date and time in one location corresponds to in one or more other locations — essential for scheduling meetings across distributed teams, coordinating releases, or figuring out when a livestream airs in your local time. Unlike a simple UTC offset, real-world timezones observe daylight saving time (DST) on different schedules (or not at all), so the offset between two cities can change throughout the year. This tool uses your browser's built-in Intl API to compute accurate conversions — including the correct DST-adjusted offset for the specific date you choose — for any combination of cities, entirely locally.
How to use
- 1Pick a date and time, and the timezone it should be interpreted in (defaults to your browser's timezone).
- 2Click "Now" at any time to reset the source to the current date and time.
- 3The equivalent local time in each listed city updates instantly, along with its UTC offset.
- 4A "+1d" or "-1d" badge appears when a city's date differs from the source date. Use "Add a timezone..." to add more cities, or the X to remove one.
Frequently asked questions
- Why does the offset between two cities sometimes change during the year?
- Because of daylight saving time (DST). Many countries shift their clocks forward or backward by an hour on different dates (or not at all), so the gap between, say, London and New York is 5 hours part of the year and 4 hours the rest, depending on each region's DST schedule.
- What does the "+1d" / "-1d" badge mean?
- It means that city's calendar date is one day ahead of or behind the source date at that moment — common when converting times near midnight across the International Date Line or into a very different UTC offset.
- How accurate is this compared to a real timezone database?
- This tool relies on your browser's built-in Intl.DateTimeFormat, which uses the IANA Time Zone Database — the same authoritative source used by most operating systems and programming languages — so conversions correctly account for historical and future DST rule changes.
- Is my selected date and time sent anywhere?
- No. All conversions are computed locally in your browser using the Intl API. Nothing is sent to a server.