# duration()

Returns an object representing a length of time.

## Signature

`duration (number num, String unit)`

## Parameters

***num*:** Type: `number`. The length of time in a given unit.

***unit***

Type: `String`

A datetime unit. The default is 'milliseconds'. The options are 'years, 'months', 'weeks', 'days', 'hour', 'minutes', 'seconds', 'milliseconds'.

## Returns

**Type: `Object`** A duration object.

## Sample Code

```javascript
var dur = $A.localizationService.duration(2, 'days');
```