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Time zone converter and world clock

Pick a time in one city and see it in New York, London, Dubai, Karachi, New Delhi, Tokyo, Sydney and anywhere else you add — with the time difference, UTC offset and daylight saving handled for you.

  • Free
  • No sign-up
  • Private — runs in your browser

How do I convert time between time zones?

  1. 1It starts with the time now in your own time zone — the clocks keep moving.
  2. 2To convert another time, change the date, the time or the time zone at the top.
  3. 3Add the cities you need, or remove the ones you don't. Your list is remembered in this browser.
  4. 4Read each city's local time, date, UTC offset and how many hours ahead or behind it is.

How is the time difference worked out?

  1. 01Time in city B = time in city A − offset of A + offset of B
  2. 02Offset = hours ahead of (+) or behind (−) UTC on that date
  3. 03Difference = offset of B − offset of A

Every time zone is a number of hours (sometimes plus 30 or 45 minutes) ahead of or behind Coordinated Universal Time (UTC). Karachi is UTC+5:00, New Delhi UTC+5:30, London UTC+0:00 in winter. To convert, the time you enter is first turned into UTC, then into each city's own offset.

Many countries move their clocks for daylight saving, on different dates. That is why the difference between, say, New York and Karachi is 10 hours in January but 9 hours in July. The converter uses the official IANA time zone database built into your browser, so each city's offset is the one in force on the date you choose.

Good to know

  • For a meeting, set the time in the organiser's city and check every city's time — look for "next day" or "previous day".
  • Check meetings near March, April, October and November: daylight saving changes on different dates in Europe and North America.
  • When sending a time by message, include the time zone or the UTC offset, e.g. 15:00 UTC+5.
  • India uses one time zone (UTC+5:30) for the whole country; China uses one (UTC+8).

Time zone converter — common questions

How do I convert time from one time zone to another?

Enter the date and time, pick the time zone it is in, and the converter shows the same moment in every city in your list, including the date if it is a different day.

What is the time difference between two cities?

Each city row shows how many hours it is ahead of or behind the time zone you picked. The difference can change during the year because of daylight saving.

Does it handle daylight saving time?

Yes. It uses the time zone rules in your browser (the IANA time zone database), so summer and winter time are applied for the exact date you choose.

What is UTC and how is it different from GMT?

UTC (Coordinated Universal Time) is the world's time standard. GMT is the time zone of the UK in winter, which is the same as UTC+0:00. In summer, the UK uses BST (UTC+1:00).

Why are some time zones 30 or 45 minutes off?

Some countries chose offsets in half or quarter hours, for example India (UTC+5:30), Iran (UTC+3:30), Nepal (UTC+5:45) and parts of Australia (UTC+9:30).

Sources

Formulas last reviewed: September 30, 2026 ·How we check our formulas

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