Temporal.PlainDate.prototype.daysInYear

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 daysInYear accessor property of Temporal.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

js
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

Specification
Temporal proposal
# sec-get-temporal.plaindate.prototype.daysinyear

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
daysInYear
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