Time Zone Converter
Convert time between any two time zones — DST handled automatically
Quick answer: New York to London is normally +5 hours (London ahead). New York to Tokyo is +13 or +14 hours. Select any pair below for the exact converted time.
DST note:
Offsets are computed for the selected date — DST transitions are applied automatically. The US springs forward on the 2nd Sunday in March; the EU on the last Sunday in March.
Key International Time Differences
| From / To | UTC Offset | DST? |
|---|---|---|
| 🇺🇸 New York (ET) | UTC−5 / −4 | Yes (Mar–Nov) |
| 🇬🇧 London (GMT/BST) | UTC+0 / +1 | Yes (Mar–Oct) |
| 🇩🇪 Berlin (CET/CEST) | UTC+1 / +2 | Yes (Mar–Oct) |
| 🇮🇳 Mumbai (IST) | UTC+5:30 | No |
| 🇨🇳 Shanghai (CST) | UTC+8 | No |
| 🇯🇵 Tokyo (JST) | UTC+9 | No |
| 🇦🇺 Sydney (AEST/AEDT) | UTC+10 / +11 | Yes (Oct–Apr) |
| 🇳🇿 Auckland (NZST/NZDT) | UTC+12 / +13 | Yes (Sep–Apr) |
Why do US and EU clocks change on different dates?
The US transitions on the 2nd Sunday in March, while Europe transitions on the last Sunday in March. This creates a 1-2 week window where the transatlantic offset shifts. For example, NY-London is 5 hours in January but briefly 4 hours right after the US spring forward before Europe follows.
Frequently Asked Questions
What is the International Date Line?
The International Date Line (IDL) runs roughly along the 180th meridian in the Pacific Ocean. Crossing it westward moves you one calendar day forward; crossing it eastward moves you one day back. This is why Auckland (UTC+12/13) and Honolulu (UTC-10) are on opposite sides of the same geographic longitude but a full day apart on the calendar.
Do all countries observe daylight saving time?
No. Most of Africa, Asia, and some South American countries do not observe DST. China uses a single time zone (CST, UTC+8) for the entire country. India (IST, UTC+5:30) does not use DST. Japan (JST, UTC+9) abolished DST in 1951. The EU voted to abolish mandatory DST transitions but the change has not yet been implemented.
What is UTC and how does it differ from GMT?
UTC (Coordinated Universal Time) is the primary world time standard. GMT (Greenwich Mean Time) is a time zone at UTC+0. In everyday use they are interchangeable, but technically UTC is an atomic time scale while GMT is based on solar time. UTC is used in aviation, computing, and international standards.