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TIME ZONES

World Clock

The current time in cities around the world, updated live, with each city's UTC offset.

See the time in several places at once

The World Clock shows the current local time, date and UTC offset for a set of cities side by side, updating once per second. It starts with a useful default spread across time zones and lets you add or remove any city with an IANA time zone your browser supports.

Day and night at a glance

Each card is marked as day or night based on the local hour (6 a.m. to 6 p.m. counts as day), which makes it quick to see, without reading the numbers, whether a city is in a reasonable hour to call or message.

Want the background? Read our comprehensive guide: Time Zones and DST for Developers.

How to use this tool

  1. Read the current time, date and offset for each city.
  2. Select Add a city to add another time zone to the list.
  3. Select Remove on a card to take it off the list.
  4. Leave the page open; every clock updates once per second on its own.

Examples

The same instant, read as two of the default cities.

New York

2026-09-21T14:42:31.000Z

Local time
10:42:31
Offset
UTC-4

London

2026-09-21T14:42:31.000Z

Local time
15:42:31
Offset
UTC+1

Tokyo

2026-09-21T14:42:31.000Z

Local time
23:42:31
Offset
UTC+9

Frequently Asked Questions

How often do the clocks update?
Once per second, using your device's own clock, so if your device's time is wrong, the displayed times will be off by the same amount.
Can I save my list of cities?
Not yet; the list resets to the default cities when you reload the page. Bookmark the page and re-add your cities, or use the Timezone Converter's comparison table for a similar side-by-side view.
How is day or night decided?
A city is shown as daytime when its local hour is between 6 a.m. and 6 p.m., and night-time otherwise. It is a simple clock-based rule, not based on actual sunrise or sunset.
Does this need an internet connection to stay accurate?
No. Once the page is loaded, the clocks run from your device's own clock and the browser's built-in time zone data, with nothing fetched from a server.

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