Temporal.Duration.prototype.years

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

You can know the sign of years by checking the duration's sign property.

The set accessor of years 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

Using years

const d1 = Temporal.Duration.from({ years: 1, months: 1 });
const d2 = Temporal.Duration.from({ years: -1, months: -1 });
const d3 = Temporal.Duration.from({ years: 1 });
const d4 = Temporal.Duration.from({ months: 12 });

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

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