World Clock

What is World Clock?

World Clock is an online tool for viewing current time in major cities worldwide in real-time. Supports 200+ cities across 24 time zones, automatically handles Daylight Saving Time (DST). Data source: IANA time zone database, update frequency <1 second. Suitable for international team collaboration, business, and travel planning.

How to Use

  1. Select or search for a city
  2. View current time and date
  3. Add multiple cities to compare times
  4. Automatically handles DST adjustments

Features

  • Supports 200+ major global cities
  • Covers 24 time zones
  • Automatically handles Daylight Saving Time (DST)
  • Real-time updates every second

FAQ

What is World Clock?

World Clock is an online tool for viewing current time in major cities worldwide in real-time. Supports 200+ cities across 24 time zones, automatically handles Daylight Saving Time (DST). Data source: IANA time zone database, update frequency <1 second.

How many cities are supported?

Supports 200+ major global cities, covering: (1) North America (New York, Los Angeles, Chicago, etc.); (2) Europe (London, Paris, Berlin, etc.); (3) Asia (Beijing, Tokyo, Singapore, etc.); (4) Oceania (Sydney, Auckland, etc.). Custom city addition supported.

Is the time zone data accurate?

Yes. Uses IANA time zone database (tz database), the global standard time zone data source. Includes historical DST rules, automatically updated. Data synchronized with operating systems, Java, Python, and other systems.

Does it support Daylight Saving Time (DST)?

Yes. Automatically handles global DST rules. Example: US DST (second Sunday in March to first Sunday in November), European DST (last Sunday in March to last Sunday in October). No manual adjustment needed.

What is the update frequency?

Updates every second. Uses JavaScript's setInterval(1000) method for real-time refresh. Based on system clock calculation, no network latency. Stops updating when page is closed.

What are the use cases?

Suitable for: (1) International team collaboration (scheduling meetings); (2) International business (contacting overseas clients); (3) Travel planning (knowing destination time); (4) Remote work (coordinating colleagues in different time zones). Supports viewing multiple cities simultaneously.

Is data uploaded to servers?

No. All time calculations are done locally in the browser using JavaScript's Date object and Intl.DateTimeFormat API. No internet connection required, protecting privacy.

Does it work on mobile?

Fully supported. Responsive design adapts to phones, tablets, and computers. Works on iOS Safari 12+, Android Chrome 80+, WeChat built-in browser. Can quickly check global time on mobile devices.