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How many US time zones are there?

The US has 6 time zones, UTC−10:00 to UTC−05:00, as of September 30, 2026. The table shows every zone at an example time, 12:00 PM in Eastern: New York; type any time or date.

Your numbers

Time zones
6

At 12:00 PM on September 30, 2026 in Eastern: New York, the US has 6 time zones and 7 UTC offsets in use.

UTC offsets in use at that moment
7
Eastern: New York
12:00 PM EDT · Wed, Sep 30 · UTC−04:00 · daylight saving
Central: Chicago
11:00 AM CDT · Wed, Sep 30 · UTC−05:00 · daylight saving
Mountain: Denver
10:00 AM MDT · Wed, Sep 30 · UTC−06:00 · daylight saving
Mountain, no DST: Phoenix, Arizona
9:00 AM MST · Wed, Sep 30 · UTC−07:00 · no daylight saving
Pacific: Los Angeles
9:00 AM PDT · Wed, Sep 30 · UTC−07:00 · daylight saving
Alaska: Anchorage
8:00 AM AKDT · Wed, Sep 30 · UTC−08:00 · daylight saving
Hawaii-Aleutian: Adak, Alaska
7:00 AM HADT · Wed, Sep 30 · UTC−09:00 · daylight saving
Hawaii-Aleutian, no DST: Honolulu
6:00 AM HST · Wed, Sep 30 · UTC−10:00 · no daylight saving

Answer for the example date Wednesday, September 30, 2026. It changes to today's date when the page loads.

Time zones: 6. At 12:00 PM on September 30, 2026 in Eastern: New York, the US has 6 time zones and 7 UTC offsets in use.

How to calculate

Lists the time zones of the US with the local time, abbreviation, UTC offset, and daylight saving in each, for any time and date.

Example with the default inputs (Time 12:00, In Eastern: New York, Date September 30, 2026) on the example date Wednesday, September 30, 2026: At 12:00 PM on September 30, 2026 in Eastern: New York, the US has 6 time zones and 7 UTC offsets in use.

Method: For the typed time in the chosen zone, find the instant (UTC) it names, then show each listed zone’s clock at that instant with its UTC offset, from the browser’s IANA time zone data.

  • The zones are IANA tzdata names from zone1970.tab (tzdata 2026a): America/New_York, America/Chicago, America/Denver, America/Phoenix, America/Los_Angeles, America/Anchorage, America/Adak, Pacific/Honolulu. The browser supplies each zone's offsets and daylight saving rules, so a rule change arrives with a browser update.
  • “Time zones” counts the different standard offsets among the listed zones. A zone’s standard offset in a year is the lower of its offsets at 00:00 UTC on January 1 and July 1 of that UTC year.
  • “UTC offsets in use” counts the different offsets the listed zones show at that moment.
  • Each zone shows its local time, the abbreviation from the browser’s Unicode CLDR English names (left out when CLDR has none), the date as “Tue, Sep 29”, the offset as UTC+hh:mm or UTC−hh:mm, and “daylight saving” when the offset is ahead of the standard offset, “standard time” when the zone’s January 1 and July 1 offsets differ but it is on the standard offset, or “no daylight saving” when they are the same. Because the rule compares January 1 and July 1, a zone that moves its offset for good during a year (Cancún in 2015, Novosibirsk in 2016), or whose January 1 falls in Morocco’s Ramadan change (Casablanca in 2030 to 2033), shows the later offset as “daylight saving” for that year.
  • A time that does not exist in the chosen zone (skipped when clocks spring forward) has no answer. A time that occurs twice (when clocks fall back) shows both moments, earlier first, where they differ.
  • Dates from 2000 to 2040 work.

Machine-readable copies: Markdown, JSON.

Worked examples

Each example is checked against the calculator on every build.

  1. Time 12:00, In Eastern: New York, Date 2026-01-15 gives Time zones 6, UTC offsets in use at that moment 6, Eastern: New York 12:00 PM EST · Thu, Jan 15 · UTC−05:00 · standard time, Central: Chicago 11:00 AM CST · Thu, Jan 15 · UTC−06:00 · standard time, Mountain: Denver 10:00 AM MST · Thu, Jan 15 · UTC−07:00 · standard time, Mountain, no DST: Phoenix, Arizona 10:00 AM MST · Thu, Jan 15 · UTC−07:00 · no daylight saving, Pacific: Los Angeles 9:00 AM PST · Thu, Jan 15 · UTC−08:00 · standard time, Alaska: Anchorage 8:00 AM AKST · Thu, Jan 15 · UTC−09:00 · standard time, Hawaii-Aleutian: Adak, Alaska 7:00 AM HAST · Thu, Jan 15 · UTC−10:00 · standard time, Hawaii-Aleutian, no DST: Honolulu 7:00 AM HST · Thu, Jan 15 · UTC−10:00 · no daylight saving.Source: IANA Time Zone Database, tzdata 2026a (https://www.iana.org/time-zones)
  2. Time 12:00, In Eastern: New York, Date 2026-07-15 gives Time zones 6, UTC offsets in use at that moment 7, Eastern: New York 12:00 PM EDT · Wed, Jul 15 · UTC−04:00 · daylight saving, Central: Chicago 11:00 AM CDT · Wed, Jul 15 · UTC−05:00 · daylight saving, Mountain: Denver 10:00 AM MDT · Wed, Jul 15 · UTC−06:00 · daylight saving, Mountain, no DST: Phoenix, Arizona 9:00 AM MST · Wed, Jul 15 · UTC−07:00 · no daylight saving, Pacific: Los Angeles 9:00 AM PDT · Wed, Jul 15 · UTC−07:00 · daylight saving, Alaska: Anchorage 8:00 AM AKDT · Wed, Jul 15 · UTC−08:00 · daylight saving, Hawaii-Aleutian: Adak, Alaska 7:00 AM HADT · Wed, Jul 15 · UTC−09:00 · daylight saving, Hawaii-Aleutian, no DST: Honolulu 6:00 AM HST · Wed, Jul 15 · UTC−10:00 · no daylight saving.Source: IANA Time Zone Database, tzdata 2026a (https://www.iana.org/time-zones)

Other questions people ask

How many time zones does the US have?

The 50 states use 6 standard time zones: Eastern (UTC−05:00), Central (UTC−06:00), Mountain (UTC−07:00), Pacific (UTC−08:00), Alaska (UTC−09:00), and Hawaii-Aleutian (UTC−10:00). US law sets nine zones in all: it adds Atlantic (Puerto Rico and the US Virgin Islands), Samoa, and Chamorro (Guam and the Northern Mariana Islands).

Which states are in two time zones?

Florida, Idaho, Indiana, Kansas, Kentucky, Michigan, Nebraska, Nevada, North Dakota, Oregon, South Dakota, Tennessee, and Texas each have counties in two of the zones. Alaska has two as well: Alaska time, and Hawaii-Aleutian time in the Aleutian Islands west of 169°30′ W.

Do Arizona and Hawaii use daylight saving time?

No. Hawaii and most of Arizona keep standard time all year, as federal law allows a state to do; the Navajo Nation in northeastern Arizona does change its clocks. So from March to November Arizona shows the same time as California, and in winter the same time as Denver.

When do US clocks change?

Daylight saving time starts at 2:00 AM local time on the second Sunday in March and ends at 2:00 AM local time on the first Sunday in November. In 2026: Sunday, March 8, 2026 and Sunday, November 1, 2026. Each zone changes at its own 2:00 AM, so for an hour two neighbouring zones are 2 hours apart in March and show the same time in November.