Time Zone Converter
Convert a date and time from one time zone to another. Runs entirely in your browser using its built-in time zone database.
Converted time
Same moment, quick reference
How it works
This tool uses your browser's built-in time zone database (the same IANA database used across virtually all modern software) to convert the moment you enter to any other time zone — correctly handling daylight saving time and each region's own offset rules, entirely locally.
A worked example
A meeting at 09:00 on 15 January 2027 in America/New_York (UTC-5) is 14:00 UTC, 19:30 in Asia/Kolkata (UTC+5:30), 23:00 in Asia/Tokyo (UTC+9) and 01:00 on 16 January in Australia/Sydney (UTC+11, because it is summer there). Move the same 09:00 meeting to 15 July and New York is UTC-4, so it becomes 13:00 UTC, 18:30 in Kolkata and 23:00 in Sydney (UTC+10). The gap between New York and India shrinks from 10.5 hours to 9.5 hours without anyone changing anything in India.
Why gaps change during the year
- The United States and Canada move their clocks on the second Sunday of March and the first Sunday of November.
- The UK and EU change on the last Sunday of March and the last Sunday of October, so for a few weeks the gap between New York and London is one hour different from usual.
- Australia, New Zealand and other southern countries use daylight saving in the opposite season.
- India, Japan, China, Singapore and the UAE do not use daylight saving at all.
Using the tool well
Pick zones by their IANA names, such as Europe/London or Asia/Kolkata. Abbreviations are ambiguous: IST can mean India, Ireland or Israel, and CST can mean US Central, China or Cuba. Some offsets are not whole hours, such as Nepal at UTC+5:45. A result can land on the previous or next day, which is normal across the date line. The offset is read for the exact date and time you enter, so daylight saving is applied correctly even on the day clocks change. On that day one local time is skipped and one is repeated: a skipped time (02:30 in New York on 8 March 2026) is moved forward to 03:30, and a repeated time (01:30 on 1 November 2026) uses its first occurrence, before the clocks go back.
Guide
- Unix Timestamps and Time Zones: Seconds vs ms — Seconds versus milliseconds, UTC versus local time, and the year 2038 limit, plus the mistakes that produce wrong dates.
Frequently asked questions
Does this account for daylight saving time?
Yes — it uses your browser's built-in IANA time zone database, which tracks each region's own daylight saving rules and historical changes, so the conversion is correct for the specific date entered, not just a fixed offset.
Is my data sent anywhere?
No — the conversion is computed entirely in your browser using standard, built-in time zone data.
Why choose Asia/Kolkata instead of IST?
Abbreviations like IST, CST and BST each refer to more than one place and don't say anything about daylight saving. IANA names such as Asia/Kolkata identify a region and carry its full rule history, so the conversion is unambiguous.
Why did my converted time land on a different day?
When two zones are far apart, the same moment can be on different calendar dates. For example, 9 pm in New York is already the next morning in Tokyo. The date shown with the result is correct.
What dates can it convert?
Real dates from the year 1 to 9999. A date that doesn't exist, such as 31 February, or a time like 25:00 shows a message instead of a result.