using .setUTCHours() it would be possible to actually set dates in UTC-time, which would allow you to use UTC-times throughout the system. You cannot set it using UTC in the constructor though, unless you specify a date-string. Using new Date(Date.UTC(year, month, day, hour, minute, second)) you can create a Date-object from a specific UTC time.
Background JavaScript’s Date object tracks time in UTC internally, but typically accepts input and produces output in the local time of the computer it’s running on. It has very few facilities for working with time in other time zones. The internal representation of a Date object is a single number, representing the number of milliseconds … Read more
tl;dr Instant.now() // Capture the current moment in UTC. Generate a String to represent that value: Instant.now().toString() 2016-09-13T23:30:52.123Z Details As the correct answer by Jon Skeet stated, a java.util.Date object has no time zone†. But its toString implementation applies the JVM’s default time zone when generating the String representation of that date-time value. Confusingly to … Read more
The time.time() function returns the number of seconds since the epoch, as a float. Note that “the epoch” is defined as the start of January 1st, 1970 in UTC. So the epoch is defined in terms of UTC and establishes a global moment in time. No matter where on Earth you are, “seconds past epoch” … Read more
-new Date().getTimezoneOffset()/60; The method getTimezoneOffset() will subtract your time from GMT and return the number of minutes. So if you live in GMT-8, it will return 480. To put this into hours, divide by 60. Also, notice that the sign is the opposite of what you need – it’s calculating GMT’s offset from your time … Read more
In general, to make a naive datetime timezone-aware, use the localize method: import datetime import pytz unaware = datetime.datetime(2011, 8, 15, 8, 15, 12, 0) aware = datetime.datetime(2011, 8, 15, 8, 15, 12, 0, pytz.UTC) now_aware = pytz.utc.localize(unaware) assert aware == now_aware For the UTC timezone, it is not really necessary to use localize since … Read more
Using an offset to calculate Timezone is a wrong approach, and you will always encounter problems. Time zones and daylight saving rules may change on several occasions during a year, and It’s difficult to keep up with changes. To get the system’s IANA timezone in JavaScript, you should use console.log(Intl.DateTimeFormat().resolvedOptions().timeZone) As of April 2022, this … Read more
DateTimeOffset is a representation of instantaneous time (also known as absolute time). By that, I mean a moment in time that is universal for everyone (not accounting for leap seconds, or the relativistic effects of time dilation). Another way to represent instantaneous time is with a DateTime where .Kind is DateTimeKind.Utc. This is distinct from … Read more
Summary of answers and other data: (please add yours) Do: Whenever you are referring to an exact moment in time, persist the time according to a unified standard that is not affected by daylight savings. (GMT and UTC are equivalent with this regard, but it is preferred to use the term UTC. Notice that UTC … Read more