---
title: duration
framework: foundation
role: symbol
role_heading: Instance Property
path: foundation/nsdateinterval/duration
---

# duration

The duration of the date interval.

## Declaration

```swift
var duration: TimeInterval { get }
```

## See Also

### Accessing Start Date, End Date, and Duration

- [startDate](foundation/nsdateinterval/startdate.md)
- [endDate](foundation/nsdateinterval/enddate.md)