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Time Zone Converter

Enter a date and time in one time zone into this time zone converter and see the same moment in as many other zones as you list, with the daylight-saving rules for that exact date. A time skipped when clocks spring forward is flagged as not existing, and a time that happens twice when they fall back shows both moments.

Date and local time in source zoneSource IANA timezoneDestination IANA zones, one per line

Times skipped by a DST change are rejected; a repeated (fall-back) hour shows both possible instants. Use IANA names such as America/New_York.

Asia/Karachi: 1/1/1970, 5:00:00 AM

America/New_York: 12/31/1969, 7:00:00 PM

Europe/London: 1/1/1970, 1:00:00 AM

How the conversion works

1. Pin the momentlocal date and time + source zone → one exact instant
2. Look up the offsetUTC = local time − the source zone's offset on that date
3. Show it everywherelocal time in each zone = UTC + that zone's offset at that instant

Offsets come from the IANA time zone database in your browser, read through the Temporal date API, so they include every daylight-saving rule and historical change for the date you pick. Each destination gets its own line in ISO 8601 form, such as 2026-11-04T14:00:00+00:00[Europe/London], which you can copy in one click.

A time skipped when clocks spring forward is rejected as not existing; a time repeated when they fall back shows both moments. An invalid destination zone shows an error on its own row. Use IANA names such as America/New_York. Under the zone list, a live clock shows the current time in each zone you've entered, and flags any name it doesn't recognize.

Need to find a time that suits a whole team instead? The Time Zone Meeting Planner compares working hours across cities and shows where they overlap.

Worked example

A 9:00 call in New York, on two Wednesdays a week apart:

Zone	Oct 28 (UTC-04:00)	Nov 4 (UTC-05:00)
Europe/London	13:00	14:00
Asia/Karachi	18:00	19:00
Asia/Kolkata	18:30	19:30
Australia/Sydney	00:00Oct 29	01:00Nov 5

Between the two dates New York leaves daylight saving (UTC-04:00 to UTC-05:00), so the call moves an hour later for everyone who doesn't change their clocks that week. London had already changed on October 25, which is why the New York–London gap is one hour shorter than usual for that one week.

Sydney is on summer time (UTC+11:00), so the call lands early the next morning there. Kolkata keeps UTC+05:30 all year, a half-hour offset.

When the clocks change in 2026

Most mistakes in time zone math happen in the weeks around these dates. The US, Europe and Australia all change on different Sundays, and southern-hemisphere zones move in the opposite direction.

Zone	2026 changes (offset at noon)
America/New_York	March 8: -05:00 → -04:00 · November 1: -04:00 → -05:00
America/Los_Angeles	March 8: -08:00 → -07:00 · November 1: -07:00 → -08:00
Europe/London	March 29: +00:00 → +01:00 · October 25: +01:00 → +00:00
Europe/Berlin	March 29: +01:00 → +02:00 · October 25: +02:00 → +01:00
Australia/Sydney	April 5: +11:00 → +10:00 · October 4: +10:00 → +11:00
Asia/Karachi	No change — UTC+05:00 all year
Asia/Kolkata	No change — UTC+05:30 all year

United States

Daylight saving starts on the second Sunday in March and ends on the first Sunday in November, at 2:00 a.m. local time. Arizona (except the Navajo Nation) and Hawaii stay on standard time, so use America/Phoenix rather than America/Denver for most of Arizona.

UK and European Union

Summer time runs from the last Sunday in March to the last Sunday in October, with every country changing at the same instant, 01:00 UTC. That's why London, Berlin and Athens stay the same distance apart all year.

Abbreviations to avoid

CST is both US Central and China Standard Time. IST is used in India, Ireland and Israel. BST is British Summer Time and Bangladesh Standard Time. "EST" is often written in summer when Eastern Daylight Time is meant. Write the IANA name or a UTC offset instead.

Sources: IANA Time Zone Database (tzdb); 15 U.S.C. § 260a (US daylight saving time); Directive 2000/84/EC on summer-time arrangements. Change dates in the table are computed from the time zone data at build time. Checked 15 October 2026.

Frequently asked questions

How do I convert a time to another time zone?+

Pick the date and local time, type the source zone as an IANA name such as America/New_York, and list the destination zones one per line. Click Convert / preview: each line shows the same moment in that zone with its UTC offset, and Copy puts the whole list on your clipboard.

What's the difference between this and the Time Zone Meeting Planner?+

This converter answers "what time is it there when it's this time here?" for one specific date and time. The Time Zone Meeting Planner answers "when can we all meet?": it lines up several cities' working hours across the day and highlights where they overlap, with a shareable link and calendar file. Use the planner to choose a slot, then this converter to double-check it or send exact times.

Does it handle daylight saving time?+

Yes, for the date you enter. Britain and the US change their clocks on different weekends, so the gap between them moves. 9:00 in New York on October 28, 2026 is 13:00 in London; a week later, on November 4, it's 14:00. A converter that uses a fixed offset gets one of those wrong.

Why was my time rejected?+

When clocks spring forward, an hour of local time is skipped: 2:30 a.m. on March 8, 2026 never happens in New York. When they fall back, an hour happens twice: 1:30 a.m. on November 1, 2026 occurs first at UTC-04:00 and again at UTC-05:00. A skipped time is rejected with a "does not exist" message, so choose a time outside the gap. A repeated time is not rejected: the converter shows both moments so you can pick the one you mean. If a destination zone name is invalid, only that row shows an error.

Why use names like America/New_York instead of EST?+

Abbreviations are ambiguous and don't say whether daylight saving applies. CST can mean US Central or China Standard Time, and IST is used in India, Ireland and Israel. An IANA name identifies a region and carries its full history of offsets and clock changes, so the result is right for any date.

Does it work with half-hour and 45-minute offsets?+

Yes. Offsets come from the time zone database, not whole hours. In the example on this page, 9:00 in New York on October 28, 2026 is 18:30 in Kolkata (UTC+05:30). Asia/Kathmandu (UTC+05:45) and Australia/Adelaide work the same way.

What does a result like 2026-10-28T13:00:00+00:00[Europe/London] mean?+

It's an ISO 8601 date and time with its UTC offset, followed by the zone name in brackets. Read it as 13:00 on October 28, 2026, London time, which is UTC+00:00 on that date. The format is unambiguous, so it's safe to paste into tickets, logs and messages.

Is UTC the same as GMT?+

For converting times, they're the same: both are offset +00:00. Strictly, UTC is the atomic-clock time standard and GMT is a time zone. The catch is that UK time isn't GMT all year — Europe/London is UTC+00:00 in January but UTC+01:00 in July, during British Summer Time. Use UTC when you mean the fixed reference, and Europe/London when you mean UK clock time.

How do I find the IANA name for a city?+

Names follow the pattern Region/City, where the city is usually a major one that keeps that clock: Asia/Kolkata covers all of India, America/Chicago US Central time and Europe/Berlin Germany. The source box suggests a few common zones as you type. A misspelled destination shows as "Invalid zone" in the live clocks, and any misspelled name stops the conversion with an error, so you won't get a silently wrong answer.

What if the converted time falls on a different day?+

Each result includes the full date, so a jump past midnight is shown, not hidden. 8:00 p.m. in New York on October 28, 2026 is 09:00 on October 29 in Tokyo. Check the date as well as the time before you send an invite across the Pacific.

Is anything I enter sent or saved?+

No. The conversion runs in your browser using its built-in time zone data, and the zones you type aren't stored — reloading the page restores the default list. The live clocks under the zone list also run locally.