Time Zone Conversions
Learn how to convert between time zones, understand UTC/GMT, daylight saving, and use world clock tools. This guide covers the essentials for global scheduling.
Introduction
Time zones are regions of the world that observe the same standard time. Converting between time zones is essential for travel, business, and online meetings.
What Are Time Zones?
- The Earth is divided into 24 time zones, each roughly 15° of longitude apart.
- Each time zone is usually one hour ahead or behind its neighbor.
UTC and GMT
- UTC (Coordinated Universal Time): The global time standard. Time zones are defined as offsets from UTC (e.g., UTC+2).
- GMT (Greenwich Mean Time): Nearly identical to UTC, used in the UK and some other regions.
Daylight Saving Time (DST)
- Some regions adjust clocks forward in spring and back in fall to make better use of daylight.
- Not all countries observe DST—always check local rules.
How to Convert Time Zones
- Find the UTC offset for both locations (e.g., New York is UTC-5, London is UTC+0).
- Calculate the time difference and add/subtract as needed.
- Account for daylight saving if applicable.
Example Conversion
- Convert 3:00 PM in New York (UTC-5) to London (UTC+0): 3:00 PM + 5 hours = 8:00 PM in London
- Convert 10:00 AM in Tokyo (UTC+9) to Los Angeles (UTC-8): 10:00 AM - 17 hours = 5:00 PM (previous day) in LA
World Clock Tools
- Use online world clocks or smartphone apps to check current times worldwide.
- Many calendar apps automatically adjust for time zones when scheduling meetings.
Tips
- Always confirm the time zone and DST status for both locations.
- When in doubt, use UTC as a reference point.
FAQ
- What is the International Date Line? The line where the date changes by one day when crossed, located at about 180° longitude.
- Why do some countries have half-hour or 45-minute offsets? Some regions set their own local time for convenience or historical reasons.