Temporal.PlainDateTime.prototype.add()

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The add() method of Temporal.PlainDateTime instances returns a new Temporal.PlainDateTime object representing this date-time moved forward by a given duration (in a form convertible by Temporal.Duration.from()).

Syntax

js
add(duration)
add(duration, options)

Parameters

duration

A string, an object, or a Temporal.Duration instance representing a duration to add to this date-time. It is converted to a Temporal.Duration object using the same algorithm as Temporal.Duration.from().

options Optional

An object containing the following property:

overflow Optional

A string specifying the behavior when a date component is out of range. Possible values are:

"constrain" (default)

The date component is clamped to the valid range.

"reject"

A RangeError is thrown if the date component is out of range.

Return value

A new Temporal.PlainDateTime object representing the date-time specified by the original PlainDateTime, plus the duration.

Exceptions

RangeError

Thrown if the result is not in the representable range, which is ±(108 + 1) days, or about ±273,972.6 years, from the Unix epoch.

Description

For how calendar durations are added, see Temporal.PlainDate.prototype.add().

Adding a duration is equivalent to subtracting its negation.

Examples

Adding a duration

js
const start = Temporal.PlainDateTime.from("2021-01-01T12:34:56");
const end = start.add({
  years: 1,
  months: 2,
  weeks: 3,
  days: 4,
  hours: 5,
  minutes: 6,
  seconds: 7,
  milliseconds: 8,
});
console.log(end.toString()); // 2022-03-26T17:41:03.008

For more examples, especially with how different calendars and the overflow option interact with calendar durations, see Temporal.PlainDate.prototype.add().

Specifications

Specification
Temporal proposal
# sec-temporal.plaindatetime.prototype.add

Browser compatibility

Report problems with this compatibility data on GitHub
desktopmobileserver
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Deno
Node.js
add
Experimental

Legend

Tip: you can click/tap on a cell for more information.

No support
No support
Experimental. Expect behavior to change in the future.
See implementation notes.
User must explicitly enable this feature.

See also