Time Zone Converter

How to convert a time between time zones

Every time zone is defined by its offset from Coordinated Universal Time (UTC): New York is UTC−05:00 in winter, Tokyo is UTC+09:00 all year. To convert a time you first turn it into UTC, then into each other zone. The catch is that many zones change their offset for daylight saving time (DST), on dates that differ from country to country, so the offset depends on the date.

1. Choose the zone the time is in. Zones are listed by city and grouped by region, with the offset on the chosen date.
2. Enter the date and time, or press Now for the current time there.
3. Choose the zones to convert to. Add more to plan a call across several offices.

The result shows the local time in each place, the date when it falls on a different day, the zone’s name and UTC offset, and how far ahead or behind the starting zone it is. To add or subtract hours rather than change zones, use the time calculator.

The conversion

offset

the zone’s difference from UTC on that date, positive east of Greenwich (UTC+05:30) and negative west (UTC−04:00)

UTC

Coordinated Universal Time, the reference time scale; it never changes for daylight saving

Not every offset is a whole number of hours. India uses UTC+05:30, Nepal UTC+05:45, parts of Australia UTC+09:30 or +10:30, and the Chatham Islands UTC+12:45 in winter, so the calculator works in minutes.

Two local times need special handling. On the night clocks spring forward, an hour is skipped: 2:30 a.m. never happens in New York on 8 March 2026. The calculator moves such a time forward by the length of the jump (to 3:30 a.m.) and says so. On the night clocks fall back, an hour repeats: 1:30 a.m. happens twice in New York on 1 November 2026. The calculator uses the first occurrence, still on daylight time, and tells you what the second would give. This is the same rule the modern JavaScript date standard (Temporal) uses by default.

Worked example

A call is set for 9:00 a.m. in New York on Thursday, 15 October 2026. What time is it elsewhere?

1. In October New York is on daylight time (EDT), UTC−04:00, so 9:00 a.m. + 4 hours = 1:00 p.m. UTC.
2. London is still on British Summer Time, UTC+01:00: 2:00 p.m., 5 hours ahead.
3. Tokyo, UTC+09:00, has no daylight saving: 10:00 p.m., 13 hours ahead.
4. Kolkata, UTC+05:30: 6:30 p.m., 9½ hours ahead. Kathmandu, UTC+05:45, would be 6:45 p.m.

The gaps are not fixed. In 2026 the US moves its clocks forward on 8 March but the UK waits until 29 March, so for those three weeks New York is only 4 hours behind London: 9:00 a.m. in New York on 20 March is 1:00 p.m. in London.

Daylight saving time and other pitfalls

• DST dates differ. The US and most of Canada change on the second Sunday in March and the first Sunday in November, at 2:00 a.m. local time. The UK and the EU change on the last Sunday in March and October, at 1:00 a.m. UTC. Much of the Southern Hemisphere does the opposite, and most of Asia and Africa doesn’t use DST at all.
• Abbreviations are ambiguous. CST can mean US Central, China or Cuba Standard Time, and IST can be India, Ireland or Israel. Pick zones by city, as here, and quote the UTC offset when you send an invitation.
• Some regions don’t follow their neighbours. Most of Arizona stays on UTC−07:00 all year, so it matches Denver in winter and Los Angeles in summer. Choose Phoenix, not Denver, for it.
• Dates change too. An evening meeting in California is the next morning in Asia. The result flags when a zone is on a different calendar day.
• Rules change. Countries adjust their zones and DST rules from time to time. The rules come from the IANA time zone database built into your browser, so keeping the browser up to date keeps them current. For whole-day differences, use the days between dates calculator.