US Time Zones Clock Widget

How it works

Each row is one US standard time zone, ordered east to west, and its time comes from the browser's IANA database for a representative zone (America/New_York for Eastern, America/Phoenix for Arizona, Pacific/Honolulu for Hawaii). The widget compares the zone's current UTC offset with its standard offset: one hour more means daylight saving time, so the label switches from EST to EDT, CST to CDT, PST to PDT or AKST to AKDT. Arizona and Hawaii stay on MST and HST all year and carry a "No DST" pill. The notice under the rows gives the next change from 15 U.S.C. 260a: clocks go forward at 2:00 a.m. on the second Sunday of March (March 14, 2027) and back on the first Sunday of November (November 1, 2026). The "Your time" pill marks the zone that contains the visitor's own device setting, including sub-zones such as America/Detroit or America/Boise. The full set adds Atlantic (Puerto Rico), the Aleutians, Samoa and Chamorro (Guam).

Method

• Offset = local wall time in the zone - UTC, read from Intl.DateTimeFormat for the zone
• Daylight saving on when offset = standard offset + 60 minutes; label = daylight abbreviation, else standard
• DST starts on the second Sunday of March: day = 1 + (7 - weekday of March 1) mod 7 + 7
• DST ends on the first Sunday of November: day = 1 + (7 - weekday of November 1) mod 7; both at 2:00 a.m. local

Worked examples

Limitations

• One representative zone per row: counties that differ from their state (parts of Indiana, Kentucky, Tennessee, Idaho, the Dakotas) are matched only through the visitor's own device setting.
• If Congress changes the DST rule, the change-date notice needs an update; the clock times themselves follow the browser's time-zone data.
• Times are only as accurate as the visitor's device clock.

Where publishers use it

• A national customer-support page showing whether the Pacific team is still within its 9-to-5
• A webinar landing page where attendees from Boston to Honolulu check what time the session is for them
• A trucking dispatcher's dashboard tracking drivers crossing from Central into Mountain time
• A Phoenix company's site reminding visitors that Arizona does not change its clocks
• A Guam or Puerto Rico business showing its own time beside the mainland zones

Questions

Sources

1. 15 U.S. Code 260a - Advancement of time or changeover dates - Legal Information Institute, Cornell Law School . DST from 2 a.m. on the second Sunday of March to 2 a.m. on the first Sunday of November; states may exempt themselves. Checked 2026-10-01.
2. 15 U.S. Code 263 - Duty of Secretary of Transportation - Legal Information Institute, Cornell Law School . Names the nine US standard time zones: Atlantic, eastern, central, mountain, Pacific, Alaska, Hawaii-Aleutian, Samoa and Chamorro. Checked 2026-10-01.
3. Time zone database - IANA . The zone data the browser uses for each row's offset.

Cite or recommend this tool

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