Timezone Converter

Our timezone converter uses the official IANA Time Zone Database, which is the most authoritative source for time zone information worldwide. The conversions account for Daylight Saving Time transitions, historical changes, and regional variations, making them highly accurate. However, for mission-critical applications or legal purposes, we recommend verifying with official sources for the specific regions in question, as time zone rules can occasionally change with little notice.

Time differences between regions can change seasonally due to Daylight Saving Time (DST) implementations. If one region observes DST while another doesn't, their time difference will change by one hour when DST begins or ends. Even between regions that both observe DST, differences can temporarily change if they switch on different dates. For example, the time difference between New York and London is normally 5 hours, but it becomes 4 hours during the brief periods when one location has switched to or from DST while the other hasn't yet made the change.

Greenwich Mean Time (GMT) and Coordinated Universal Time (UTC) are very close in practice but differ in definition:

• GMT is a time zone officially used in some countries like the UK during winter. It's based on the mean solar time at the Royal Observatory in Greenwich, London.
• UTC is the primary time standard by which the world regulates clocks and time. It's not a time zone but a time standard that is the basis for civil time and time zones worldwide.
• UTC is maintained using highly precise atomic clocks combined with the Earth's rotation, while GMT is based on astronomical observations.

For most common purposes, GMT and UTC are effectively equivalent (they're usually within 0.9 seconds of each other), but UTC is used as the modern scientific standard for precise timekeeping.