America/Whitehorse time zone
5:56AMMST
MSTUTC−7−2 h vs New York (you)
No transitions: America/Whitehorse stays on MST (UTC−7).
About America/Whitehorse
America/Whitehorse is the IANA time zone for MST: Yukon (east) in Canada. It currently keeps Mountain Standard Time (MST, UTC−7) all year.
Its principal location is Whitehorse at 60.72° N, 135.05° W.
Abbreviations in use: MST. Offset page: UTC−7.
Rule for future years (POSIX TZ string)
MST7
The standard time is called MST and is UTC−7. POSIX writes the offset with the opposite sign (west of Greenwich is positive), which is why the string says "7". There is no daylight saving rule: the zone stays on this offset for every year after the end of its explicit transitions. Software that has no full tzdata copy, such as many embedded devices, can use this string directly as the TZ environment variable.
History of America/Whitehorse since 1970
The record starts with local mean time (UTC−9), which ended on August 20, 1900. The first daylight saving time in the record is in 1918.
| Years | Clocks | Abbreviations |
|---|---|---|
| 1970–1979 | UTC−8 all year | PST |
| 1980–2019 | UTC−8 in winter, UTC−7 in summer | PST, PDT |
| 2020 | UTC−8 until March 8, then UTC−7 | PST, PDT, MST |
| 2021 onward | UTC−7 all year | MST |
Before 1970
9 offset changes before 1970 in the record:
- Sunday, April 14, 1918: UTC−9 → UTC−8 (YDT), daylight saving time
- Sunday, October 27, 1918: UTC−8 → UTC−9 (YST)
- Sunday, May 25, 1919: UTC−9 → UTC−8 (YDT), daylight saving time
- Saturday, November 1, 1919: UTC−8 → UTC−9 (YST)
- Monday, February 9, 1942: UTC−9 → UTC−8 (YWT), daylight saving time
- Sunday, September 30, 1945: UTC−8 → UTC−9 (YST)
- Sunday, April 25, 1965: UTC−9 → UTC−7 (YDDT), daylight saving time
- Sunday, October 31, 1965: UTC−7 → UTC−9 (YST)
- Sunday, February 27, 1966: UTC−9 → UTC−8 (PST)
Changes of the winter (standard) offset: Sunday, March 8, 2020, UTC−8 → UTC−7.
tzdata commits to accuracy from 1970 for every zone (zone1970.tab); earlier entries are historical research and may be incomplete.
Aliases and zones with the same clock
These older or country-specific IDs are links to America/Whitehorse in tzdata. Their pages redirect here: Canada/Yukon.
Other zones that keep exactly the same time under the current rules (but have a different history): America/Dawson, America/Dawson_Creek, America/Fort_Nelson, America/Hermosillo, America/Mazatlan, America/Phoenix, America/Vancouver.
Convert Whitehorse time
Using America/Whitehorse in code
Every major platform reads the same IANA ID. Store instants in UTC and convert with the ID at display time; never store a fixed offset for a place that has daylight saving time.
// JavaScript
new Date().toLocaleString('en-US', { timeZone: 'America/Whitehorse' })
# Python 3.9+
from zoneinfo import ZoneInfo
from datetime import datetime
datetime.now(ZoneInfo('America/Whitehorse'))
// Java
java.time.ZonedDateTime.now(java.time.ZoneId.of("America/Whitehorse"))
// Go
loc, _ := time.LoadLocation("America/Whitehorse")
time.Now().In(loc)
-- PostgreSQL
SELECT now() AT TIME ZONE 'America/Whitehorse';
# Shell
TZ='America/Whitehorse' datePlatforms ship their own copy of tzdata and update it on their own schedule. After a rule change, outputs can differ until the platform updates; this page uses tzdata 2026f.