Time Zone Converter
Enter a date and time, select your source and target time zones, and convert instantly.
Major Time Zone Reference
| City / Region | IANA Zone | UTC Offset (Standard) |
|---|---|---|
| Los Angeles | America/Los_Angeles | UTC−8 |
| New York | America/New_York | UTC−5 |
| São Paulo | America/Sao_Paulo | UTC−3 |
| London | Europe/London | UTC+0 |
| Paris / Berlin | Europe/Paris | UTC+1 |
| Moscow | Europe/Moscow | UTC+3 |
| Dubai | Asia/Dubai | UTC+4 |
| Mumbai | Asia/Kolkata | UTC+5:30 |
| Singapore | Asia/Singapore | UTC+8 |
| Tokyo | Asia/Tokyo | UTC+9 |
| Sydney | Australia/Sydney | UTC+10 |
| Auckland | Pacific/Auckland | UTC+12 |
Offsets shown for standard time. DST shifts typically add +1 hour in summer for affected regions.
Frequently Asked Questions
What are IANA time zone names?
IANA (Internet Assigned Numbers Authority) time zones are the standard identifiers for time zones used by operating systems, browsers, and programming languages. They follow the format Continent/City — for example, America/New_York, Europe/London, or Asia/Tokyo. They are preferred over abbreviations like EST or PST because abbreviations are ambiguous (EST is used in both North America and Australia).
How does the converter handle Daylight Saving Time?
The converter uses your browser's built-in Intl.DateTimeFormat API, which automatically applies Daylight Saving Time (DST) rules for the selected time zone on the entered date. So if you convert a summer date in New York, it will correctly show EDT (UTC−4) rather than EST (UTC−5).
What is UTC offset?
UTC (Coordinated Universal Time) is the primary time standard by which the world regulates clocks. UTC offset is the number of hours and minutes a time zone differs from UTC. For example, New York is UTC−5 in winter (EST) and UTC−4 in summer (EDT). London is UTC+0 in winter (GMT) and UTC+1 in summer (BST).
Why might two adjacent cities be in different time zones?
Political and geographic factors shape time zone boundaries. Countries often choose time zones for national unity, economic reasons, or to align with a major trading partner. For example, China uses a single time zone (UTC+8) despite spanning five geographic zones, and Indiana historically had counties in different time zones.
What is the International Date Line?
The International Date Line is an imaginary line at approximately 180° longitude where the calendar date changes. Cross it heading east and you go back a day; cross it heading west and you advance a day. This is why a flight from Los Angeles to Tokyo can arrive before it departs in local time — you cross the date line westbound.