🌐 Time Zone Converter
By ToolNimba Editorial Team · Updated 2026-06-19
This time zone converter turns a time in one place into the matching time somewhere else. Enter the date and time, choose the zone you are starting from and the zone you want to convert to, and you get the converted time along with the offset for each zone. It is handy for scheduling a call, catching a live event, or working out when a flight actually lands. The conversion uses your browser built-in time zone data, so daylight saving shifts are handled automatically for the date you pick.
What is the Time Zone Converter?
A time zone is a region that keeps the same standard time, defined as an offset from Coordinated Universal Time (UTC). New York in winter runs at UTC minus 5 hours, London at UTC plus 0, and Tokyo at UTC plus 9. To convert a time you first work out the exact instant it represents (its UTC value), then express that same instant using the offset of the destination zone. The wall clock changes, but the underlying moment stays the same, which is why two people in different zones can join the same call at the same instant while their clocks read different numbers.
The part that trips people up is daylight saving time (DST). Many regions move their clocks forward in spring and back in autumn, so a zone offset is not fixed: New York is UTC minus 5 in winter (EST) and UTC minus 4 in summer (EDT). Because of this, the gap between two cities can change depending on the date. London and New York are usually 5 hours apart, but for a few weeks each year, when the two regions switch on different dates, the gap is briefly 4 hours. A reliable converter uses the actual rules for the specific date you enter rather than a single fixed offset.
This tool relies on the IANA time zone database that ships with every modern browser, accessed through the Intl.DateTimeFormat interface. Zones are named by a representative city, such as America/New_York or Asia/Dhaka, rather than by abbreviations like EST or BST, because abbreviations are ambiguous (several zones share them) and they do not capture the DST rules. By naming a region and a date, the browser can look up the correct offset for that exact moment, including historical and future DST changes, so the result matches what a clock in that city would really show.
When to use it
- Scheduling a video call with colleagues or clients in another country without doing the math in your head.
- Working out the local start time of a live stream, sports match, or product launch announced in a different zone.
- Planning travel: knowing what time it will be at your destination when you land, or when to call home.
- Coordinating a deadline across a distributed team so everyone agrees on the same cutoff instant.
How to use the Time Zone Converter
- Enter the date for the time you want to convert.
- Enter the clock time as it reads in the source location.
- Pick the From time zone (where that time is local).
- Pick the To time zone you want the time converted into.
- Read the converted time, the offset for each zone, and the difference between them. Use Swap to reverse the direction or Use now to fill the current moment.
Formula & method
Worked examples
It is 9:00 AM on 19 June 2026 in New York. What time is it in London?
- In June, New York is on daylight time (EDT), offset UTC minus 4.
- Convert to UTC: 9:00 AM plus 4 hours = 1:00 PM UTC.
- London in June is on summer time (BST), offset UTC plus 1.
- Add the offset: 1:00 PM UTC plus 1 hour = 2:00 PM in London.
Result: 9:00 AM in New York is 2:00 PM in London (5 hours ahead).
It is 12:00 noon UTC on 15 January 2026. What time is it in New York?
- The instant is already 12:00 noon UTC.
- In January, New York is on standard time (EST), offset UTC minus 5.
- Apply the offset: 12:00 noon UTC minus 5 hours = 7:00 AM.
- No DST adjustment applies because winter uses standard time.
Result: 12:00 noon UTC is 7:00 AM in New York on that date.
Common time zones and their standard (winter) UTC offsets
| Zone (IANA) | City | Standard offset | Observes DST |
|---|---|---|---|
| UTC | Coordinated Universal Time | UTC+00:00 | No |
| America/Los_Angeles | Los Angeles | UTC-08:00 | Yes |
| America/New_York | New York | UTC-05:00 | Yes |
| Europe/London | London | UTC+00:00 | Yes |
| Europe/Berlin | Berlin | UTC+01:00 | Yes |
| Asia/Dhaka | Dhaka | UTC+06:00 | No |
| Asia/Tokyo | Tokyo | UTC+09:00 | No |
| Australia/Sydney | Sydney | UTC+10:00 | Yes |
Common mistakes to avoid
- Using a fixed offset and ignoring daylight saving. Many zones change their offset twice a year. New York runs at UTC minus 5 in winter and UTC minus 4 in summer, so a single fixed offset is not reliable. The gap to London is usually 5 hours, but for the few weeks each year when the two regions switch on different dates it briefly becomes 4 hours. Always convert for the specific date, which this tool does for you.
- Confusing the source and destination zones. The From zone is where your entered time is local, and the To zone is where you want the answer. Swapping them flips the result. Use the Swap button if you set them the wrong way round.
- Trusting zone abbreviations like CST or IST. Abbreviations are ambiguous: CST can mean US Central, China Standard, or Cuba Standard time, and IST can mean India, Ireland, or Israel. Naming a region by city, as this tool does, removes the guesswork.
- Forgetting the date can roll over. A late evening in Tokyo can be the previous morning in Los Angeles. Check the weekday and date in the result, not just the clock time, when a conversion crosses midnight.
Glossary
- UTC
- Coordinated Universal Time, the global reference time from which every zone is measured as a positive or negative offset.
- Time zone offset
- The difference between a zone local time and UTC, written like UTC+09:00 or UTC-05:00.
- Daylight saving time (DST)
- The practice of moving clocks forward in spring and back in autumn, which temporarily changes a zone offset.
- IANA time zone
- A named region in the standard time zone database, such as America/New_York, carrying the full history of that area offset and DST rules.
- Wall clock time
- The time a clock on the wall shows in a given place, as opposed to the underlying universal instant.
Frequently asked questions
How do I convert time from one time zone to another?
Enter the date and the clock time as it reads in the source location, choose the From zone and the To zone, and the converter shows the matching time in the destination zone. It also displays the UTC offset for each zone and the difference between them.
Does this tool handle daylight saving time?
Yes. It uses the IANA time zone database built into your browser, which knows the daylight saving rules for each region. The offset is looked up for the exact date you enter, so spring and autumn clock changes are applied automatically.
Why are zones named by city instead of by abbreviation?
Abbreviations such as CST or IST are ambiguous and shared by several zones, and they do not capture daylight saving rules. Naming a representative city like America/New_York or Asia/Tokyo pins down both the offset and the DST behaviour for that region.
What is UTC and why does it matter?
UTC, Coordinated Universal Time, is the global reference clock. Every time zone is defined as an offset from UTC. Converting between two zones works by translating the source time to its UTC instant, then expressing that same instant in the destination zone.
Why is the time difference between two cities not always the same?
Because regions start and end daylight saving on different dates, the gap between two cities can shift by an hour for a few weeks each year. Converting for the specific date you care about gives the correct difference rather than a single fixed number.
Is my data sent anywhere when I convert a time?
No. The whole conversion runs in your browser using the local time zone data that ships with it. Nothing you type is uploaded, and the tool works offline once the page has loaded.