liminfo

World Clock

Free web tool: World Clock

Seoul

Sat, Apr 11

20:53:18

Tokyo

Sat, Apr 11

20:53:18

Beijing

Sat, Apr 11

19:53:18

Hong Kong

Sat, Apr 11

19:53:18

Singapore

Sat, Apr 11

19:53:18

Bangkok

Sat, Apr 11

18:53:18

Mumbai

Sat, Apr 11

17:23:18

Dubai

Sat, Apr 11

15:53:18

Moscow

Sat, Apr 11

14:53:18

Istanbul

Sat, Apr 11

14:53:18

London

Sat, Apr 11

12:53:18

Paris

Sat, Apr 11

13:53:18

Berlin

Sat, Apr 11

13:53:18

New York

Sat, Apr 11

07:53:18

Chicago

Sat, Apr 11

06:53:18

LA

Sat, Apr 11

04:53:18

Hawaii

Sat, Apr 11

01:53:18

Sydney

Sat, Apr 11

21:53:18

Auckland

Sat, Apr 11

23:53:18

Sao Paulo

Sat, Apr 11

08:53:18

About World Clock

The World Clock displays the current local time in 20 major cities around the world, updated every second in real time. Cities covered include Seoul, Tokyo, Beijing, Hong Kong, Singapore, Bangkok, Mumbai, Dubai, Moscow, Istanbul, London, Paris, Berlin, New York, Chicago, Los Angeles, Hawaii, Sydney, Auckland, and Sao Paulo. Each city card shows the local time, the current date (with day of week), and a sun or moon icon indicating whether it is daytime or nighttime at that location.

You can switch between two display modes: digital and analog. In digital mode, each city shows the time in HH:MM:SS 24-hour format alongside the date. In analog mode, each city's card renders a live SVG clock face with hour, minute, and second hands that update in real time. The second hand is drawn in red for easy visibility, while the hour and minute hands adapt to the dark or light theme. This analog display is particularly useful for getting an intuitive sense of time across multiple zones at a glance.

The World Clock is essential for remote workers, international project teams, frequent travelers, and anyone who regularly communicates across borders. Knowing at a glance whether it is business hours, late evening, or the middle of the night in a counterpart's city prevents scheduling mistakes and shows respect for colleagues' time zones. All timing uses the JavaScript Intl.DateTimeFormat API with IANA timezone identifiers, ensuring accurate DST-aware local times for every city without any server interaction.

Key Features

  • 20 cities across all inhabited continents: Asia, Europe, Americas, Pacific, Middle East
  • Live time updates every second using JavaScript setInterval
  • Day/night icon (sun or moon) based on local hour for each city
  • Digital display mode: HH:MM:SS 24-hour format with date and weekday
  • Analog display mode: live SVG clock faces with hour, minute, and red second hands
  • One-click toggle between digital and analog modes for all 20 clocks simultaneously
  • Bilingual Korean/English city names and date formatting using locale-aware Intl.DateTimeFormat
  • 100% client-side rendering — no server requests, dark mode support, works on mobile

Frequently Asked Questions

Which cities are shown on the World Clock?

The World Clock covers 20 cities: Seoul (KR), Tokyo (JP), Beijing (CN), Hong Kong (HK), Singapore (SG), Bangkok (TH), Mumbai (IN), Dubai (AE), Moscow (RU), Istanbul (TR), London (GB), Paris (FR), Berlin (DE), New York (US), Chicago (US), Los Angeles (US), Hawaii (US), Sydney (AU), Auckland (NZ), and Sao Paulo (BR).

How often does the time update?

The displayed time updates every second. The tool uses React's useState with a setInterval that fires every 1000 milliseconds, calling setNow(new Date()) to refresh the current time. Each city card then recalculates its local time from the updated UTC timestamp using Intl.DateTimeFormat with the appropriate IANA timezone.

How does the day/night icon work?

Each city's clock card shows a sun icon if the local hour is between 6 and 17 (daytime), and a moon icon if the hour is outside that range (nighttime). The hour is extracted from the Intl.DateTimeFormat output for that specific timezone, so it correctly reflects local day and night regardless of your device's timezone.

What is the difference between the digital and analog display modes?

Digital mode shows the current time in HH:MM:SS 24-hour format alongside a short date string (e.g., "Mon, Jan 6"). Analog mode replaces the time text with an SVG clock face that shows hour, minute, and second hands moving in real time. Both modes update every second for all 20 cities simultaneously.

Does the World Clock account for daylight saving time?

Yes. The clock uses IANA timezone identifiers (e.g., Europe/London, America/New_York) with the JavaScript Intl.DateTimeFormat API, which automatically applies the correct DST offset based on the current date. Cities like London switch between GMT and BST automatically, and New York switches between EST and EDT, without any manual adjustment needed.

What is the time difference between Seoul and London?

Seoul (KST, UTC+9) and London vary depending on whether UK daylight saving is in effect. During British Summer Time (BST, UTC+1, roughly late March to late October), the difference is 8 hours. During GMT (UTC+0, late October to late March), the difference is 9 hours.

What is the time difference between Seoul and New York?

Seoul (KST, UTC+9) and New York differ based on US daylight saving time. When Eastern Daylight Time (EDT, UTC-4) is in effect (March to November), the difference is 13 hours. When Eastern Standard Time (EST, UTC-5) applies (November to March), the difference is 14 hours.

Can I use this World Clock on my phone?

Yes. The World Clock is fully responsive and works on smartphones and tablets. The grid layout adapts from one column on narrow screens to two columns on medium screens and three columns on larger displays, ensuring all 20 city cards are clearly readable on any device.