Time Zone Lookup

An IANA identifier is a stable, unambiguous name for a time zone, written as Area/Location such as Europe/London or Asia/Tokyo. Unlike abbreviations such as EST, IANA identifiers never change meaning with daylight saving time, which is why software and servers rely on them.

UTC is the modern time standard that the world's clocks are set against. GMT is a time zone fixed at UTC+0 used in the UK, while EST is a US eastern time zone that shifts with daylight saving time. Abbreviations are ambiguous because they mean different things in different places.

Large countries like Russia, the United States, and Australia span enough longitude that a single clock time would put noon in the middle of the night somewhere. They split into multiple zones so local time stays roughly aligned with daylight.

Daylight saving time shifts clocks forward during part of the year to move an extra hour of evening daylight into the working day. It is a political choice, not a geographic one, so it varies by country and can change — which is why offsets are listed separately from standard time.

UTC+05:30 means local time is five hours and thirty minutes ahead of UTC. India and Sri Lanka use this offset year-round. To convert, add the offset to UTC — when it is 12:00 UTC, it is 17:30 in India.