World Clock

How to use the world clock

The list opens with the local time of this device at the top, followed by eight major cities. Each row shows the current time with ticking seconds, the date, the UTC offset, the difference from local time, and a sun or moon icon for daytime or night. The 12h and 24h buttons switch the clock format for the whole page.

To add a place, type a city or time zone name such as Mumbai, Chicago or Europe/Berlin and pick a result. The search covers every IANA time zone the browser supports, plus common city names without a zone of their own, such as San Francisco or Beijing. Edit list shows buttons to move a city up or down or to remove the city. The list stays saved in this browser and loads again on the next visit.

Converting a time between cities

The time converter takes a date and a time in one city and lists the matching time in every other city on the list. Planning a call between London and Singapore works this way: pick London, enter 09:00, and the table shows 16:00 or 17:00 in Singapore, depending on the time of year. The conversion follows the daylight saving time rules for the chosen date, so a meeting in late March or late October shows the right hour.

Why the difference from local time changes

Many countries switch to daylight saving time, and they switch on different dates. The United States moves its clocks in March and November, Europe on the last Sundays of March and October, and India, Japan and China keep the same offset all year. For a few weeks each year, the gap between New York and London is four hours instead of five. The clock reads the time zone rules built into the browser, so these shifts show up without any manual change.

Day and night indicator

The sun icon appears between 06:00 and 18:00 local time in each city, and the moon icon covers the night hours. The icon gives a quick sense of whether a colleague is likely at work or asleep. Actual sunrise and sunset times depend on latitude and season.