Master American Time
Like Never Before

The Eastern Time Zone covers the eastern United States including New York City, Miami, Boston, Atlanta, and Washington D.C. It's the most populous time zone in the U.S.

The Central Time Zone includes Chicago, Dallas, Houston, New Orleans, and much of the Midwest. It spans from the Great Lakes to Texas.

The Mountain Time Zone covers Denver, Phoenix, Salt Lake City, and Albuquerque. Arizona notably does not observe Daylight Saving Time.

The Pacific Time Zone includes Los Angeles, San Francisco, Seattle, and Las Vegas. It's home to Hollywood and Silicon Valley.

The Alaska Time Zone covers most of Alaska, including Anchorage, Fairbanks, and Juneau. The westernmost Aleutian Islands use Hawaii time.

Hawaii and the western Aleutian Islands of Alaska use this time zone. Hawaii does not observe Daylight Saving Time.

How DST works in the U.S., the exact start and end dates, why Arizona and Hawaii sit it out, and where current legislation stands.

EST vs EDT, CST vs CDT, and every other U.S. abbreviation in one reference — with the rule for choosing the right one in writing.

What UTC is, why it replaced GMT, and how to translate between UTC and any U.S. zone without getting tripped up by DST.

Practical decision rules for picking meeting times that work for coast-to-coast teams without burning anyone's morning or evening.

State-by-state breakdown — including the states split between two zones and the counties that don't follow their state's default.