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World Clock

View current time across multiple timezones

Toggle 12h/24h format

Added cities will appear below.

A world clock answers a question that comes up constantly once you work with people elsewhere: what time is it there right now? This tool puts an unlimited number of city clocks side by side and updates them every second, with a search box for adding cities, a one-click button for your own zone, a 12/24-hour toggle, and a daylight-saving marker on every card. Four cities — New York, London, Tokyo, and Shanghai — are loaded by default.

How to Use

  1. Type a city or country into the search box and click a result to add its clock. Results show the city, country, and standard UTC offset.
  2. Click Add my time to pin your own timezone for comparison against the rest.
  3. Use the toggle to switch between 24-hour (the default) and 12-hour display; the change applies to every card at once.
  4. Remove a card with the small close button in its top-right corner. There is no cap on how many cards you can keep.

How the Clocks Stay Correct

Each card is rendered from the browser’s Intl.DateTimeFormat with the city’s IANA timezone identifier. That API reads the timezone database shipped with your browser and operating system, the same registry that knows historical offset changes and the exact date each region springs forward or falls back. The visible time therefore reflects daylight saving automatically, even though the small offset label is a fixed standard-time value. The page recomputes all cards on a one-second interval, so seconds advance in step rather than drifting.

Reading a Clock Card

Every card carries the same five pieces of information: the city name, the country, the current time in large type, the calendar date, and a footer with the zone abbreviation, the standard UTC offset, and a DST marker when applicable. The date is important — a card showing 23:00 in Tokyo may already be the next calendar day where you are, and the date line disambiguates that.

Worked Example: Scheduling Across Three Cities

It is 09:00 on a Monday in New York during standard time (UTC-5). London is on GMT (UTC+0), so it is 14:00 there. Tokyo is UTC+9, so it is 23:00. Shanghai is UTC+8, so it is 22:00. A meeting at 09:00 New York therefore lands at 23:00 Tokyo — late but still workable.

Now run the same 09:00 New York time in summer, when New York is on EDT (UTC-4) and London is on BST (UTC+1). New York to London stays five hours, so London is 14:00. Tokyo has no daylight saving, so it drops to 22:00, and Shanghai to 21:00. The New York–Tokyo gap changed from 14 hours to 13 without anyone touching a setting. That seasonal shift is exactly what the DST marker warns you about.

Daylight Saving Edge Cases

  • The Southern Hemisphere runs the opposite schedule. Sydney shifts in October and April, so the Sydney–Los Angeles gap changes at different times of year than the London–New York gap.
  • Some regions never shift. China, India, Japan, and most of Africa keep a single offset year-round, so their distance from DST-observing cities changes twice a year.
  • A few zones use half-hour or 45-minute offsets. India is UTC+5:30 and Nepal is UTC+5:45; the search results show these fractional offsets so you are not surprised by a card reading :30 or :45.
  • The abbreviation in the corner is informational. Because abbreviations collide — CST means both US Central and China Standard Time — rely on the time and the city name rather than the three-letter code.

Accuracy and Limits

The time is only as accurate as your device clock, which is typically synced by the operating system to within a second. DST transitions come straight from the browser’s timezone data, so a very old browser with a stale database could be wrong for a recently changed region. The searchable city list is curated rather than global, and the tool does not compute future or past dates — it shows the present moment. For scheduling a specific future meeting, use a planner that can cross-reference everyone’s calendars.

Practical Tips for Distributed Teams

The fastest way to find a meeting slot is to add every participant’s city, then scan for where working hours overlap. If New York is UTC-5 and Berlin is UTC+1, the six-hour standard gap means a 09:00 New York call is 15:00 Berlin — comfortable for both. Add San Francisco at UTC-8 and the same 09:00 start is 06:00 there, so a 12:00 New York start (18:00 Berlin, 09:00 San Francisco) is the compromise.

  • Keep a UTC card pinned as a neutral reference. When you quote a time in a document, write both the local time and the UTC time so readers in any zone can convert.
  • Revisit the pinned list when daylight saving changes, because a slot that worked all winter can fall outside business hours in summer.
  • Remember that the date can differ. A 22:00 call in Los Angeles is already tomorrow in Tokyo, so always include the day when scheduling across the international date line.
  • Use the 12/24-hour toggle to remove ambiguity. A meeting noted only as “7:00” can be read either way; 19:00 or 7:00 PM cannot.

Frequently Asked Questions

The clock says the right time but the offset label still reads EST in summer — which is correct?

The displayed time is the authoritative one. It comes from the browser's IANA timezone data, so it already includes daylight saving. The abbreviation and UTC offset in the corner are the zone's standard base values, and the 'DST' marker next to them tells you a seasonal shift is active. Treat the time as correct and the label as the standard-time reference.

Can I add any city in the world, or only a fixed list?

The search covers a curated list of roughly 38 major cities and their countries across every populated region and both hemispheres. It is not a full gazetteer — a small town with no IANA zone of its own will not appear. Add the nearest listed city in the same zone instead.

Why did two cities that were six hours apart become seven overnight?

Because daylight saving starts and ends on different dates in different countries, and some regions do not observe it at all. New York and London are five hours apart year-round, but New York and Tokyo range from 13 to 14 hours apart as US daylight saving switches on and off.

Does the clock keep ticking while the browser tab is in the background?

The page updates once a second, but browsers throttle timers in hidden tabs. When you return, each card is recalculated from the current system time rather than counting up from where it paused, so it shows the correct time immediately.

What timezone does the 'Add my time' button use?

It reads the browser's resolved IANA zone, the same identifier your operating system reports. If your device is set to a city zone, you get that city; if it is set to a UTC offset, the card may be limited. The button is the fastest way to anchor every other clock against your own.

Is the displayed time based on my device clock?

Yes. The tool reads your system clock once per second and converts it to each selected zone. If your device clock is wrong, every card is wrong by the same amount, so check the UTC card first when something looks off.

Reviewed by the HandyTools Hub team · Last updated