metadata
title: Date.prototype.toISOString()
short-title: toISOString()
slug: Web/JavaScript/Reference/Global_Objects/Date/toISOString
page-type: javascript-instance-method
browser-compat: javascript.builtins.Date.toISOString
sidebar: jsref
The toISOString() method of {{jsxref("Date")}} instances returns a string representing this date in the date time string format, a simplified format based on ISO 8601, which is always 24 or 27 characters long (YYYY-MM-DDTHH:mm:ss.sssZ or ±YYYYYY-MM-DDTHH:mm:ss.sssZ, respectively). The timezone is always UTC, as denoted by the suffix Z.
{{InteractiveExample("JavaScript Demo: Date.prototype.toISOString()")}}
const event = new Date("05 October 2011 14:48 UTC");
console.log(event.toString());
// Expected output: "Wed Oct 05 2011 16:48:00 GMT+0200 (CEST)"
// Note: your timezone may vary
console.log(event.toISOString());
// Expected output: "2011-10-05T14:48:00.000Z"
Syntax
toISOString()
Parameters
None.
Return value
A string representing the given date in the date time string format according to universal time. It's the same format as the one required to be recognized by {{jsxref("Date.parse()")}}.
Exceptions
- {{jsxref("RangeError")}}
- : Thrown if the date is invalid or if it corresponds to a year that cannot be represented in the date string format.
Examples
Using toISOString()
const d = new Date(0);
console.log(d.toISOString()); // "1970-01-01T00:00:00.000Z"
Specifications
{{Specifications}}
Browser compatibility
{{Compat}}
See also
- {{jsxref("Date.prototype.toLocaleDateString()")}}
- {{jsxref("Date.prototype.toString()")}}
- {{jsxref("Date.prototype.toUTCString()")}}