This feature is not Baseline because it does not work in some of the most widely-used browsers.
The Temporal.Now namespace object contains static methods for getting the current time in various formats.
Unlike most global objects, Temporal.Now is not a constructor. You cannot use it with the Math object).
Most fundamentally, the system time is returned by the operating system as a time since the Unix epoch (usually millisecond-level precision, but might be nanosecond-level too). Temporal.Instant object.
An instant can be interpreted in a time zone (which is the system time zone Temporal.Now.zonedDateTimeISO(). You can also get different parts of the date and time, using Temporal.Now.plainDateTimeISO().
For example, if the computer is set to the time zone "America/New_York", Temporal.Now.zonedDateTimeISO() returns a zoned date-time like: 2021-08-01T10:40:12.345-04:00[America/New_York]. In this case, Temporal.Now.plainTimeISO() would return the time part of this zoned date-time: 10:40:12.345. However, if you call Temporal.Now.plainTimeISO("UTC"), it returns the time part of the zoned date-time in the UTC time zone: 14:40:12.345. This is especially useful for cross-system communication where the other end may be expecting the time in a different time zone.
To offer protection against timing attacks and fingerprinting, the precision of the Temporal.Now functions might get rounded depending on browser settings. In Firefox, the privacy.reduceTimerPrecision preference is enabled by default and defaults to 2ms. You can also enable privacy.resistFingerprinting, in which case the precision will be 100ms or the value of privacy.resistFingerprinting.reduceTimerPrecision.microseconds, whichever is larger.
For example, with reduced time precision, the result of Temporal.Now.instant().epochMilliseconds will always be a multiple of 2, or a multiple of 100 (or privacy.resistFingerprinting.reduceTimerPrecision.microseconds) with privacy.resistFingerprinting enabled.
/ reduced time precision (2ms) in Firefox 60
Temporal.Now.instant().epochMilliseconds;
/ Might be:
/ 1519211809934
/ 1519211810362
/ 1519211811670
/ …
/ reduced time precision with `privacy.resistFingerprinting` enabled
Temporal.Now.instant().epochMilliseconds;
/ Might be:
/ 1519129853500
/ 1519129858900
/ 1519129864400
/ …
Temporal.Now[Symbol.toStringTag]The initial value of the Object.prototype.toString().
Temporal.Now.instant()
Experimental
Returns the current time as a Temporal.Instant object.
Temporal.Now.plainDateISO()
Experimental
Returns the current date as a Temporal.PlainDate object, in the ISO 8601 calendar and the specified time zone.
Temporal.Now.plainDateTimeISO()
Experimental
Returns the current date and time as a Temporal.PlainDateTime object, in the ISO 8601 calendar and the specified time zone.
Temporal.Now.plainTimeISO()
Experimental
Returns the current time as a Temporal.PlainTime object, in the specified time zone.
Temporal.Now.timeZoneId()
Experimental
Returns a time zone identifier representing the system's current time zone.
Temporal.Now.zonedDateTimeISO()
Experimental
Returns the current date and time as a Temporal.ZonedDateTime object, in the ISO 8601 calendar and the specified time zone.
| Specification |
|---|
| Temporal # sec-temporal-now-object |