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World Clock

View the current time across multiple cities.

Your clocks (3)

New York

UTC-4:01

09:38:31 AM

Sat, May 23

London

UTC+0:59

02:38:31 PM

Sat, May 23

Tokyo

UTC+8:59

10:38:31 PM

Sat, May 23

Times update every second and are calculated by your browser using its time-zone database. Your chosen cities are saved in this browser only.

Processed on your device. We never see your files.

How to use World Clock

What this tool does

This world clock shows the current time in several cities at once. You build your own list by picking cities from a curated menu of common time zones, and each one appears as a card with its name, live time, the local date, and the city’s current UTC offset. Every card ticks forward each second, so the page is always showing the real time — not a snapshot from when you loaded it.

The clock for your own time zone is marked, making it easy to compare “now” at home against “now” everywhere else on your list. Your selection is remembered in this browser, so the cities you care about are there next time you visit.

Use cases

A world clock earns its place the moment you work or talk across time zones. Use it to find a meeting slot that is reasonable for colleagues in different regions, to know whether it is a polite hour to message family or friends abroad, or to track market and business hours in other countries. Travelers can keep a card for home and a card for their destination side by side. Remote teams can pin the cities of everyone on the team, so a glance answers “is it the middle of the night for them?” before a call gets scheduled. It is also simply handy for following live events — sport, launches, broadcasts — that are announced in another region’s local time.

How to use it

  1. Open the Add a city menu and choose a city. The list only shows cities you have not already added.
  2. Click Add city. A live clock card appears in the grid below.
  3. Repeat for every place you want to track. Cards reflow to fit your screen.
  4. To remove a city, click the × on its card.
  5. The card for your own time zone is labelled “your time zone” so you always have a reference point.

The time on each card updates every second on its own — there is nothing to refresh. Because the time is read from the system clock each tick, a card stays correct even if the tab was in the background for a while.

Privacy & your data

Your list of cities is stored in this browser only, using local storage. It is not sent to any server, there is no account, and there is no cloud sync or cross-device access. That keeps the tool private and fast, but it also means the list is tied to this specific browser: clearing your browsing data, using private or incognito mode, or switching to another browser or device will reset the tool to its default cities. If your set of cities is important, it takes only a few seconds to rebuild — treat the saved list as a convenience, not a permanent record.

All time and offset calculations are done locally by your browser’s built-in date functions, so nothing about which cities you watch ever leaves your device.

Tips

Add your own city first and leave it at the top so every comparison has an anchor. When you are hunting for a meeting time, scan the cards for any that show early-morning or late-night hours — those are the people for whom the slot is awkward. Watch the UTC offset line as well as the time: it tells you exactly how far apart two cities are, and it shifts automatically when a region enters or leaves daylight saving, which is a common source of scheduling mistakes. Because the cities you pick are saved locally, set up the list once for the people and places you deal with regularly, and it will be waiting for you on each visit.

Frequently asked questions

How accurate is the time shown?
Each clock is derived from your device's own clock and your browser's built-in time-zone database, then updated every second. So accuracy depends on your computer being set to the correct time — if your system clock is off, every city will be off by the same amount. The time-zone offsets, including ones with half-hour and 45-minute differences, come from the standard IANA database your browser ships.
Does it handle daylight saving time?
Yes. The clocks use IANA time zones rather than fixed offsets, so daylight saving changes are applied automatically. A city like London or New York will show the correct offset whether or not summer time is in effect, and the displayed UTC offset updates accordingly.
Where is my list of cities saved?
Your selected cities are stored in this browser only, in its local storage. There is no cloud sync and no cross-device access. If you clear your browser data, use private browsing, or open the tool in a different browser or device, you will see the default set of cities again.
Why isn't my city in the list?
The picker offers a curated set of around thirty common cities so the menu stays short and easy to scan. Each entry represents a time zone, so a nearby city in the list will usually share your exact time. The labels are chosen to cover the major regions and offsets people most often need.
Is anything sent to a server?
No. All time calculations happen in your browser using JavaScript's built-in Intl date functions. Your chosen cities never leave your device, and nothing about your usage is uploaded or tracked.

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