Temporal.ZonedDateTime.prototype.offsetNanoseconds

The offsetNanoseconds accessor property of {{jsxref("Temporal.ZonedDateTime")}} instances returns an integer representing the offset used to interpret the internal instant, as a number of nanoseconds (positive or negative). The value is a safe integer because it's less than a day, which is 8.64e15 nanoseconds.

The set accessor of offsetNanoseconds is undefined. You cannot change this property directly. Use the {{jsxref("Temporal/ZonedDateTime/with", "with()")}} method to create a new Temporal.ZonedDateTime object with the desired new {{jsxref("Temporal/ZonedDateTime/offset", "offset")}} value (which will change this property too), or use the {{jsxref("Temporal/ZonedDateTime/withTimeZone", "withTimeZone()")}} method to create a new Temporal.ZonedDateTime object in another time zone.

Examples#

Using offsetNanoseconds#

const dt = Temporal.ZonedDateTime.from(
  "2021-07-01T12:00:00-07:00[America/Los_Angeles]",
);
console.log(dt.offsetNanoseconds); // -25200000000000

const dt2 = Temporal.ZonedDateTime.from(
  "2021-07-01T12:00:00+08:00[Asia/Shanghai]",
);
console.log(dt2.offsetNanoseconds); // 28800000000000

const dt3 = Temporal.ZonedDateTime.from(
  "1900-01-01T00:00:00+00:09:21[Europe/Paris]",
);
console.log(dt3.offsetNanoseconds); // 561000000000

Here's one way to get a ZonedDateTime representing the same wall-clock time in UTC:

const dt = Temporal.ZonedDateTime.from(
  "2021-07-01T12:00:00-07:00[America/Los_Angeles]",
);
const dtInUTC = dt.add({ nanoseconds: dt.offsetNanoseconds });
console.log(dtInUTC.withTimeZone("UTC").toString()); // "2021-07-01T12:00:00+00:00[UTC]"

Here's a better way to get the same result:

const dt = Temporal.ZonedDateTime.from(
  "2021-07-01T12:00:00-07:00[America/Los_Angeles]",
);
const dtInUTC = dt.toPlainDateTime().toZonedDateTime("UTC");
console.log(dtInUTC.toString()); // "2021-07-01T12:00:00+00:00[UTC]"

Specifications#

{{Specifications}}

Browser compatibility#

{{Compat}}

See also#

• {{jsxref("Temporal.ZonedDateTime")}}
• {{jsxref("Temporal/ZonedDateTime/with", "Temporal.ZonedDateTime.prototype.with()")}}
• {{jsxref("Temporal/ZonedDateTime/withTimeZone", "Temporal.ZonedDateTime.prototype.withTimeZone()")}}
• {{jsxref("Temporal/ZonedDateTime/offset", "Temporal.ZonedDateTime.prototype.offset")}}
• {{jsxref("Temporal/ZonedDateTime/timeZoneId", "Temporal.ZonedDateTime.prototype.timeZoneId")}}