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Time & Date · Time

Time Zone Converter

Convert a date and time from one time zone to another — daylight saving included.

Defaults to your current local time. Interpreted in the “From” zone.
From zone
To zone
Converted time

Pick a date and time to convert.

To convert a time between zones, find each zone’s offset from UTC and add the difference. For example, 3 PM in New York (UTC−5) is 8 PM in London (UTC+0), a gap of +5 hours. The exact gap shifts twice a year as daylight saving time starts and ends, so always convert against a specific date.

How a time zone conversion works

Every time zone is defined as an offset from Coordinated Universal Time (UTC) — the worldwide reference clock. New York runs at UTC−5 in winter, Tokyo at UTC+9 all year, and London at UTC+0 in winter. To move a time from one zone to another you convert it to UTC first, then apply the destination zone’s offset. The difference between the two offsets is how many hours forward or back the clock jumps.

This converter reads the offsets straight from your browser’s built-in IANA time zone database, the same data your operating system uses. That means it knows each region’s daylight saving rules and the exact dates they change, so the result is correct for the specific day you enter rather than a fixed average.

  1. 1
    Pick the source time. Enter the date and time as it reads on the clock in the “From” zone. The field defaults to your current local time.
  2. 2
    Choose the two zones. Set the “From” zone where the time is now and the “To” zone you want it in — for example New York to London.
  3. 3
    Convert to UTC. The tool subtracts the source offset to get the absolute instant. 3 PM New York (UTC−5) becomes 8 PM UTC.
  4. 4
    Apply the target offset. It then adds the destination offset. 8 PM UTC + 0 hours = 8 PM London, so 3 PM in New York is 8 PM in London.
  5. 5
    Read the offset note. The hint shows the hour gap for that date, with daylight saving already factored in.

Common cities and their typical UTC offset

Standard-time offsets; many shift by an hour during daylight saving (DST), so treat these as a guide rather than fixed values.

CityIANA zoneTypical offsetDST?
Los AngelesAmerica/Los_AngelesUTC−8Yes (→ −7)
New YorkAmerica/New_YorkUTC−5Yes (→ −4)
LondonEurope/LondonUTC+0Yes (→ +1)
Berlin / ParisEurope/BerlinUTC+1Yes (→ +2)
IstanbulEurope/IstanbulUTC+3No
DubaiAsia/DubaiUTC+4No
MumbaiAsia/KolkataUTC+5:30No
BeijingAsia/ShanghaiUTC+8No
TokyoAsia/TokyoUTC+9No
SydneyAustralia/SydneyUTC+10Yes (→ +11)

Daylight saving and planning across zones

The trickiest part of time zones is that the gap between two cities is not constant. Daylight saving time moves clocks forward an hour in spring and back in autumn, but countries do it on different dates — and some, like Türkiye, China, and India, do not observe it at all. This converter handles those shifts automatically, because it evaluates each zone’s offset on the exact date you enter rather than assuming a year-round value.

Planning a call or class across zones? Convert the proposed time in your own zone to each participant’s zone and check that it lands in waking hours for everyone. For a recurring meeting, re-check it around late March and late October — that is when daylight saving transitions can quietly shift the overlap by an hour. Picking a fixed reference like “14:00 UTC” avoids the ambiguity entirely.

Does this converter handle daylight saving time?
Yes. It reads each zone’s offset from your browser’s IANA database for the exact date you enter, so a spring or autumn clock change is applied automatically. That is why converting the same wall-clock time in January and in July can give different results.
What is the difference between UTC and GMT?
For everyday conversions they are the same reference point: UTC+0. UTC (Coordinated Universal Time) is the modern atomic-clock standard, while GMT (Greenwich Mean Time) is the older astronomical one. Note that London uses GMT only in winter — it shifts to UTC+1 during British Summer Time.
Why do time-zone offsets change during the year?
Many regions observe daylight saving time, moving their clocks forward an hour in spring and back in autumn to make better use of daylight. New York is UTC−5 in winter but UTC−4 in summer, so the gap to a non-DST zone like Tokyo changes by an hour twice a year.
How do I plan a call across several time zones?
Convert your proposed time into each person’s zone and confirm it falls within reasonable hours for everyone. For recurring meetings, anchor to a single zone (or to UTC) and re-check the overlap after each daylight saving transition in late March and late October.
What is an IANA time zone?
An IANA zone is a named region like “America/New_York” or “Asia/Kolkata” in the global time zone database. Each name carries that region’s full history and future of offset and daylight saving rules, which is why it is more reliable than a fixed label like “EST”.
Why does Mumbai show a half-hour offset?
Not every zone is a whole number of hours from UTC. India uses UTC+5:30 nationwide, and a few places such as Nepal (UTC+5:45) use 45-minute offsets. The converter accounts for these fractional offsets exactly.