About USTimeZonesMap
USTimeZonesMap is an independent reference site dedicated to one practical task: making US time zones easy to read, convert, and reason about. The site exists because time zone information across the United States is scattered across government pages, encyclopedias, and tool sites that rarely show everything in one place at once — so the goal here is to put the clocks, the map, the converter, and the explanatory content side by side.
Who the site is for
The audience is anyone who deals with US time differences on a regular basis: people scheduling meetings across coasts, families coordinating calls between states, travelers comparing local and home time, remote workers checking when colleagues are reachable, students looking up daylight saving rules, and casual readers curious about why the country has six time zones in the first place.
No account is required to use anything on the site. Every tool runs in the browser and reads time from the visitor's own device clock, so the experience is the same whether someone arrives once or returns daily.
What the site covers
- Live clocks for the six US time zones: Eastern, Central, Mountain, Pacific, Alaska, and Hawaii-Aleutian.
- An interactive map with approximate zone boundaries and major-city markers.
- A time converter for instant point-to-point conversions between any two US zones.
- A business hours calculator that shows when standard 9-to-5 windows overlap between two zones.
- Reference pages on daylight saving time, state-by-state zone assignments, abbreviations like EST and EDT, US territories, and the history of US time standardization.
How content is produced
Time zone definitions, offsets, and daylight saving rules are based on the IANA Time Zone Database, which is the same source used by major operating systems and programming languages. Clocks and conversions are computed in-browser using the visitor's local environment, which keeps the time accurate to whatever the device itself has synchronized to.
Written content — the explanatory pages and FAQ entries — is produced from publicly available reference material (government statutes, the IANA database, encyclopedias, and historical records on US time standardization). Where a statistic appears, it reflects general public-domain data, not proprietary research. Where rules can change (most relevantly, daylight saving legislation), the corresponding pages are reviewed and updated.
Editorial approach
Three things guide what goes on the site:
- Accuracy first. Anything specific — UTC offsets, DST start and end dates, state assignments — is checked against authoritative sources before publication.
- Plain language. Time zone topics are easy to overcomplicate; the writing aims for short paragraphs and direct answers rather than jargon.
- No filler. Pages are kept as long as the topic genuinely requires and no longer.
How the site is funded
USTimeZonesMap is free to use. Hosting and development are supported by display advertising served through Google AdSense. Ads do not influence which topics are covered or how zones, rules, and history are described. For more on how advertising and cookies work on the site, see the privacy policy and cookie policy.
Contact
Corrections, feedback, and questions are welcome. The fastest way to get in touch is through the contact page.