---
title: NSTimeIntervalSince1970
framework: foundation
role: symbol
role_heading: Global Variable
path: foundation/nstimeintervalsince1970
---

# NSTimeIntervalSince1970

The number of seconds from 1 January 1970 to the reference date, 1 January 2001.

## Declaration

```swift
var NSTimeIntervalSince1970: Double { get }
```

## Discussion

Discussion 1 January 1970 is the epoch (or starting point) for Unix time.

## See Also

### Getting Time Intervals

- [timeIntervalSince(_:)](foundation/nsdate/timeintervalsince(_:).md)
- [timeIntervalSinceNow](foundation/nsdate/timeintervalsincenow.md)
- [timeIntervalSinceReferenceDate](foundation/nsdate/timeintervalsincereferencedate-swift.property.md)
- [timeIntervalSince1970](foundation/nsdate/timeintervalsince1970.md)
- [timeIntervalSinceReferenceDate](foundation/nsdate/timeintervalsincereferencedate-swift.type.property.md)