Online Clock · World Time
World time at a glance: a large-type clock showing the current time and date in each time zone, with multiple zones side by side, digital or analog faces, 12/24-hour format, seconds and fullscreen. Great for desktops, classrooms and meeting rooms.
Double-click the clock area to enter or exit fullscreen
How to Use
- Open the page to see the current time on your device — no setup required.
- Add the time zones you care about under "Display Settings" — each one becomes its own clock at the same level. Click × to remove one.
- Switch the clock style or 12/24-hour format as needed, or hide the seconds, date and dark display to keep it minimal.
- When you want a wall clock, click "Fullscreen" or double-click the clock area to use browser fullscreen; click "Page Fullscreen" to fill the current page instead. Press Esc or click the × in the top-right corner to exit.
Features
- Large time display: clear, bold digits that stay readable from a distance
- Digital or analog face: switch anytime, with a small numeric readout on the analog dial
- Multiple time zones at once: add up to 8 cities across Asia, Europe, the Americas, Oceania and Africa
- 12/24-hour format: switch to suit your habit, with AM/PM shown automatically in 12-hour mode
- Date and seconds: show or hide them freely for a cleaner look
- Dark display: reduces glare at night or on large screens
- Two fullscreen modes: browser fullscreen fills the whole display, while page fullscreen covers only the current page — also works inside embedded pages and iframes
- Settings persist: time zone and display preferences are saved locally and restored next time
- Works offline: runs entirely in your browser, no network requests and no data uploaded
Typical Use Cases
Meeting rooms and classrooms
Go fullscreen and leave it on the room TV or projector so everyone can see the time at each location at a glance.
Live streams and screen recording
Dark display plus the analog face keeps the picture calm; hiding seconds cuts visual noise.
Remote team stand-ups
Show headquarters and teammates' cities side by side to check who is already at work before scheduling.
Cross-border support and on-call shifts
Put the cities for each shift side by side so handover times need no mental arithmetic.
About the Online Clock
What is an online clock?
An online clock is a digital clock that runs in your browser. Open the page and you immediately see the current time — no software to install. It reads your device system time and displays the date and time in the time zone recognized by the browser, making it handy whenever a phone or watch is out of reach.
How do time zones work?
The world is divided into more than twenty time zones, so the local time differs from place to place at any given moment. This clock converts time using the IANA time zone database (such as Asia/Shanghai, Europe/London or America/New_York), so switching zones shows the actual local time there instead of a fixed hour offset.
Why are time zone borders not straight lines?
In theory every 15° of longitude is one hour, but real borders follow administrative boundaries and often deviate for convenience. China spans five geographic zones yet uses Beijing time (UTC+8) everywhere; India is UTC+5:30, Nepal UTC+5:45 and central Australia UTC+9:30 — offsets that cannot be converted in whole hours. That is why the IANA time zone, not longitude, is the reliable reference.
What is the difference between UTC, GMT and local time?
GMT (Greenwich Mean Time) is based on Earth's rotation and was long the world time standard; UTC (Coordinated Universal Time) is kept by atomic clocks and stays close to Earth's rotation through leap seconds, and time zones are now defined relative to UTC. Local time is UTC plus the zone offset — Beijing time, for example, is UTC+8. In casual speech GMT and UTC are close enough, but logs and APIs should use UTC.
UTC offset and daylight saving time
The UTC+8 below the clock is the offset from Coordinated Universal Time (UTC). Some countries observe daylight saving time (DST), which changes the offset once a year — New York, for example, is UTC-5 in winter and UTC-4 in summer. The time zone data handles these changes automatically.
Where daylight saving time came from
Daylight saving time (DST) shifts clocks forward an hour to make better use of long summer days and was first adopted during World War I to save energy. Parts of Europe, North America and Australia still observe it, changing twice a year; China used DST from 1986 to 1991 before abolishing it. Not every region takes part — countries near the equator usually have no need — so two cities both labelled UTC+1 may actually differ in summer and winter.
How accurate is the time?
The clock shows your device system time. Modern computers and phones usually sync with network time servers via NTP, keeping the error within milliseconds. If the time looks clearly wrong, your device clock is probably misconfigured — calibrate the system time first.
Common City Offsets
UTC offsets for a few frequently used cities; the value in parentheses applies during daylight saving time.
| City | Standard offset | Daylight saving |
|---|---|---|
| London | UTC+0:00 | UTC+1:00 |
| Paris | UTC+1:00 | UTC+2:00 |
| New York (EST/EDT) | UTC-5:00 | UTC-4:00 |
| Los Angeles (PST/PDT) | UTC-8:00 | UTC-7:00 |
| Dubai | UTC+4:00 | Not observed |
| Beijing | UTC+8:00 | Not observed |
| Tokyo | UTC+9:00 | Not observed |
| Sydney | UTC+10:00 | UTC+11:00 |
Daylight saving is not universal; the clock above is the source of truth for the current offset.
Frequently Asked Questions
Yes, completely free. No sign-up or login is required, and there is no usage limit. All settings are stored locally in your browser.
Yes. Choose a target city under "Display Settings" and click "Add"; that zone appears as its own clock alongside the others. You can add up to 8 and remove any of them with ×.
Yes. World time means the local time in every zone at the same moment; each clock here converts in real time using IANA time zones, so add the cities you care about side by side and you get a complete world time board.
Some time zones use 30-minute or 45-minute offsets — India is UTC+5:30 and Nepal is UTC+5:45, for example. The clock follows real time zone rules and never rounds to whole hours.
Click "Fullscreen" below the clock, or double-click the clock area, to enter browser fullscreen. If you only want to fill the current page, click "Page Fullscreen" — it does not use the browser fullscreen API, so it also works inside an iframe. Press Esc or click the close button in the top-right corner to exit.
No. The time zone list, clock style, 12/24-hour format, seconds, date and dark display are saved in your browser and restored automatically the next time you open the page.
While the page is open it updates once a second by changing text only, with no network requests. Browsers automatically throttle updates when the tab is hidden or closed.
Because your device time zone differs from the common time zone of the country or region your connection is in. Both are shown so you can compare them; click × to remove the one you do not need, and your choice is remembered.
The list covers commonly used IANA cities. If your device time zone is not among them, the page adds it to the dropdown automatically, and you can keep the default clock as is.
This tool reads the system time of the device you are using and converts it to the selected time zone. A mismatch usually means one device has not synced its clock, or the two devices have different time zone settings. Check that automatic time sync is enabled.