County Maps US

Tools Elevation, time and sun

World Time Zone Map

Click anywhere on the map to read the zone name, its offset and whether daylight saving time is in effect there today.

How to use it

  1. Wait a moment for the map to colour itself by the UTC offset in effect today.
  2. Click any point on land or sea for the IANA zone, its long name, offset and local time.
  3. Use the legend to match a colour to an offset, and the cards below for live clocks in major cities.

How it works

The zone raster is computed in your browser from the tz-lookup library, sampled every half degree (about 35 miles at the Equator) between 60 degrees south and 84 degrees north, and drawn as strips of equal offset. Boundaries are therefore stepped and a town on a zone line can be coloured a few miles wrong. Colours are keyed by the offset in force when the page loaded, so a zone that changes its clocks later today keeps its colour until you reload.

The offset, DST state and local time of every click and every card come from the browser’s Intl time zone database, which is updated with the browser. Ocean areas use the nautical Etc/GMT zones and are drawn fainter.

Questions

How many time zones are there in the world?
By offset there are 38 in use, from UTC-12 to UTC+14, including the half-hour zones of India, Iran, Afghanistan and parts of Australia and the quarter-hour zones of Nepal and the Chatham Islands. By legal region there are more than 400 IANA zones, because places with the same offset can have different daylight saving rules.
Why is the coloured edge jagged?
The colouring is sampled on a grid rather than drawn from exact boundaries, which keeps the page small and free of a boundary download. Click the spot you care about: the click uses the exact lookup.
Does the map handle daylight saving time?
Yes. Each click and each clock asks the browser for the offset at this moment, so a zone on summer time shows its summer offset and is marked as such.

All map tools, free and without an account. Location data is processed in your browser and by the open geocoding services named on the sources page; nothing is stored by this site.