County Maps US

Tools Elevation, time and sunUS only

US Time Zone Map

Six zones across the states, plus the places that do not observe daylight saving time. Click a spot for its zone, offset and the time right now.

How to use it

  1. Wait a moment for the map to colour itself by zone.
  2. Click anywhere in the United States for the zone name, its offset from UTC and the local time.
  3. Read the cards below the map: one per zone, each with a clock ticking in that zone and a note on daylight saving.

How it works

The colouring is computed in your browser: the tz-lookup library, a compressed raster of the world’s time zone boundaries, is sampled every quarter of a degree (about 15 miles) across the states and territories and each run of the same zone is drawn as a strip. That is why the edges look stepped; a county on a zone line can appear a few miles on the wrong side. No boundary file is downloaded.

Every time, offset and daylight-saving flag comes from the browser’s own Intl time zone database for an IANA zone such as America/New_York or America/Phoenix, never from a hard-coded offset, so the cards are right on the day the clocks change. Daylight saving is detected by comparing the zone’s January and July offsets with the offset now.

Questions

How many time zones does the United States have?
Six across the fifty states (Eastern, Central, Mountain, Pacific, Alaska and Hawaii-Aleutian) and three more in the territories (Atlantic for Puerto Rico and the US Virgin Islands, Samoa and Chamorro), nine in all.
Which states do not observe daylight saving time?
Hawaii and most of Arizona. The Navajo Nation inside Arizona does change its clocks. Puerto Rico, the US Virgin Islands, Guam, the Northern Mariana Islands and American Samoa also stay on standard time all year.
Which states are split between two zones?
Florida, Indiana, Kentucky, Michigan, Tennessee, Texas, Kansas, Nebraska, North Dakota, South Dakota, Oregon, Idaho and Alaska each have counties or communities on a different zone from the rest of the state. Click the map near a line to see which side a place falls on.

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.