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Temporal.Duration.prototype.days

Limited availability

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

The days accessor property of Temporal.Duration instances returns an integer representing the number of days in the duration.

Unless the duration is balanced, you cannot assume the range of this value, but you can know its sign by checking the duration's sign property. If it is balanced to a unit above days, the days absolute value's range depends on the calendar (how many days are in a week or month).

The set accessor of days is undefined. You cannot change this property directly. Use the with() method to create a new Temporal.Duration object with the desired new value.

Examples

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Using days

const d1 = Temporal.Duration.from({ weeks: 1, days: 1 });
const d2 = Temporal.Duration.from({ weeks: -1, days: -1 });
const d3 = Temporal.Duration.from({ weeks: 1 });
const d4 = Temporal.Duration.from({ days: 7 });

console.log(d1.days); // 1
console.log(d2.days); // -1
console.log(d3.days); // 0
console.log(d4.days); // 7

// Balance d4
const d4Balanced = d4.round({
  largestUnit: "weeks",
  relativeTo: Temporal.PlainDate.from("2021-01-01"), // ISO 8601 calendar
});
console.log(d4Balanced.days); // 0
console.log(d4Balanced.weeks); // 1

Specifications

Browser compatibility

Desktop Mobile Server
Chrome Edge Firefox Opera Safari Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet WebView Android WebView on iOS Bun Deno Node.js
days 144 144 139 No preview 144 139 No No No 144 No ? 1.40 No

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Temporal/Duration/days