Date.prototype.toISOString()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The toISOString() method of 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.

Try it

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

js
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 Date.parse().

Exceptions

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()

js
const d = new Date(0);

console.log(d.toISOString()); // "1970-01-01T00:00:00.000Z"

Specifications

Specification
ECMAScript® 2027 Language Specification
# sec-date.prototype.toisostring

Browser compatibility

desktop mobile server
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
Bun
Deno
Node.js
toISOString
Chrome – Full support
Chrome 3 (Release date: 2009-09-15)
footnote Full support
Edge – Full support
Edge 12 (Release date: 2015-07-29)
footnote Full support
Firefox – Full support
Firefox 1 (Release date: 2004-11-09)
footnote Full support
Opera – Full support
Opera 10.5 (Release date: 2010-03-02)
footnote Full support
Safari – Full support
Safari 4 (Release date: 2009-06-08)
footnote Full support
Chrome Android – Full support
Chrome Android 18 (Release date: 2012-06-27)
footnote Full support
Firefox for Android – Full support
Firefox for Android 4 (Release date: 2011-03-29)
footnote Full support
Opera Android – Full support
Opera Android 11 (Release date: 2011-03-22)
footnote Full support
Safari on iOS – Full support
Safari on iOS 3.2 (Release date: 2010-04-03)
footnote Full support
Samsung Internet – Full support
Samsung Internet 1 (Release date: 2013-04-27)
footnote Full support
WebView Android – Full support
WebView Android 4.4 (Release date: 2013-12-09)
footnote Full support
WebView on iOS – Full support
WebView on iOS 3.2 (Release date: 2010-04-03)
footnote Full support
Bun – Full support
Bun 1 (Release date: 2023-09-08)
footnote Full support
Deno – Full support
Deno 1 (Release date: 2020-05-13)
footnote Full support
Node.js – Full support
Node.js 0.10 (Release date: 2013-03-11)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also