About World Clock

Displays live-updating clocks for multiple cities worldwide on a customizable dashboard. Ships with seven default cities (UTC, New York, LA, London, Paris, Tokyo, Sydney) and lets you add from a pool of 25+ cities spanning every inhabited continent. Each clock card shows time, date, time zone abbreviation, GMT offset, DST status, and the difference from your local time. Toggle 12/24-hour format, show/hide seconds and dates, and export the full clock state as JSON.

• 25+ cities available: covers North America, South America, Europe, Asia, Africa, Middle East, and Oceania
• Time computed via Intl.DateTimeFormat with IANA time zone identifiers, with fallback to manual UTC offset calculation
• DST detection compares January and July timezone name formatting to identify active daylight saving
• Display toggles: 24-hour/12-hour format, show/hide seconds, show/hide date
• Each card shows city name, formatted time, date, timezone abbreviation, GMT offset badge, DST indicator, and local time difference
• Add cities via a searchable modal; remove individual cities with a trash button
• Export produces a JSON file with current time, date, offset, and DST status for all displayed clocks

Frequently Asked Questions

How does it detect daylight saving time?

It formats the same timezone in January and July using Intl.DateTimeFormat with timeZoneName: ‘long’. If the two formatted names differ (e.g., “Eastern Standard Time” vs. “Eastern Daylight Time”), DST is active for that zone.

Can I add a city not in the list?

Not directly—the tool uses a fixed set of 25+ IANA time zones. It covers the world’s major population centers. Cities sharing a timezone with one already listed will show identical times.