# Date.toISOString()

The toISOString() method returns a string in simplified extended ISO format (ISO 8601), which is always 24 or 27 characters long (YYYY-MM-DDTHH:mm:ss.sssZ or ±YYYYYY-MM-DDTHH:mm:ss.sssZ, respectively)

```javascript
var 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 <a href="#syntax" id="syntax"></a>

```javascript
dateObj.toISOString()
```

**Return value**

A string representing the given date in the [ISO 8601](http://en.wikipedia.org/wiki/ISO_8601) format according to universal time.

## Examples <a href="#examples" id="examples"></a>

#### Using `toISOString()` <a href="#using_toisostring" id="using_toisostring"></a>

```javascript
var today = new Date('05 October 2011 14:48 UTC');

console.log(today.toISOString()); // Returns 2011-10-05T14:48:00.000Z
```

The above example uses parsing of a non–standard string value that may not be correctly parsed in non–Mozilla browsers.

## Polyfill

This method was standardized in ECMA-262 5th edition. Engines which have not been updated to support this method can work around the absence of this method using the following shim:

```javascript
if (!Date.prototype.toISOString) {
  (function() {

    function pad(number) {
      if (number < 10) {
        return '0' + number;
      }
      return number;
    }

    Date.prototype.toISOString = function() {
      return this.getUTCFullYear() +
        '-' + pad(this.getUTCMonth() + 1) +
        '-' + pad(this.getUTCDate()) +
        'T' + pad(this.getUTCHours()) +
        ':' + pad(this.getUTCMinutes()) +
        ':' + pad(this.getUTCSeconds()) +
        '.' + (this.getUTCMilliseconds() / 1000).toFixed(3).slice(2, 5) +
        'Z';
    };

  }());
}
```

## References <a href="#references" id="references"></a>

{% embed url="<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString>" %}

## Contributors to this page <a href="#contributors-to-this-page" id="contributors-to-this-page"></a>

Uros Durdevic


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