---
title: capacity
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/capacity
---

# capacity

The maximum number of elements this array can hold without having to reallocate its storage.

## Declaration

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

## Discussion

Discussion note: O(1)