---
title: startIndex
framework: Swift
role: symbol
role_heading: Instance Property
platforms: [iOS 27.0+, iPadOS 27.0+, Mac Catalyst 27.0+, macOS 27.0+, tvOS 27.0+, visionOS 27.0+, watchOS 27.0+]
path: swift/uniquearray/startindex
---

# startIndex

The position of the first element in a nonempty array. This is always zero.

## Declaration

```swift
var startIndex: Int { get }
```

## Discussion

Discussion note: O(1)