Convert time between any two timezones instantly.
A timezone is a region of the world that observes a uniform standard time. The world is divided into 24 main timezones, each roughly corresponding to 15 degrees of longitude. Timezones are expressed as offsets from Coordinated Universal Time (UTC), which is the primary time standard used worldwide.
UTC (Coordinated Universal Time) is the modern standard and serves as the basis for all timezone offsets. GMT (Greenwich Mean Time) is essentially the same as UTC but is a historical timezone rather than a standard. For practical purposes, UTC and GMT can be used interchangeably. Timezones east of UTC have positive offsets (e.g. UTC+8 for Manila) while those to the west have negative offsets (e.g. UTC-5 for New York).
Many countries observe Daylight Saving Time (DST), where clocks are set forward one hour during summer months to make better use of daylight. This means that the UTC offset for a timezone can change twice a year. This converter automatically accounts for DST using your browser's built-in timezone data.
A UTC offset is the difference in hours and minutes between a timezone and UTC. For example, Philippine Standard Time (PST) is UTC+8, meaning it is 8 hours ahead of UTC.
The International Date Line is an imaginary line at roughly 180° longitude where the calendar date changes. When you cross it heading east, you go back one day. When you cross it heading west, you go forward one day.
Most timezones are offset by whole hours, but some countries use half-hour or quarter-hour offsets for historical, political, or geographical reasons. For example, India uses UTC+5:30 and Nepal uses UTC+5:45.