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javascript instance accessor property

Temporal.PlainDate.prototype.daysInYear

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The daysInYear accessor property of PlainDate instances returns a positive integer representing the number of days in the year of this date. It is calendar-dependent.

For the ISO 8601 calendar, this is 365, or 366 in a leap year. In other calendar systems, it likely differs, especially in non-solar calendars.

The set accessor of daysInWeek is undefined. You cannot change this property directly.

Examples

Using daysInYear

const date = Temporal.PlainDate.from("2021-07-01");
console.log(date.daysInYear); // 365

const date2 = Temporal.PlainDate.from("2020-07-01");
console.log(date2.daysInYear); // 366; 2020 is a leap year

const date3 = Temporal.PlainDate.from("2021-07-01[u-ca=chinese]");
console.log(date3.daysInYear); // 354

const date4 = Temporal.PlainDate.from("2023-07-01[u-ca=chinese]");
console.log(date4.daysInYear); // 384; 2023 is a Chinese leap year

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also