---
title: "firstIndex(of:)"
framework: swift
role: symbol
role_heading: Instance Method
path: "swift/repeated/firstindex(of:)"
---

# firstIndex(of:)

Returns the first index where the specified value appears in the collection.

## Declaration

```swift
func firstIndex(of element: Self.Element) -> Self.Index?
```

## Parameters

- `element`: An element to search for in the collection.

## Return Value

Return Value The first index where element is found. If element is not found in the collection, returns nil.

## Discussion

Discussion After using firstIndex(of:) to find the position of a particular element in a collection, you can use it to access the element by subscripting. This example shows how you can modify one of the names in an array of students. var students = ["Ben", "Ivy", "Jordell", "Maxime"] if let i = students.firstIndex(of: "Maxime") {     students[i] = "Max" } print(students) // Prints "["Ben", "Ivy", "Jordell", "Max"]" note: O(n), where n is the length of the collection.