How to capitalize the first letter of a string

Swift version: 5.6

Paul Hudson    @twostraws    May 28th 2019

If you want to capitalize the first letter of a string without touching the rest of the letters, add this simple extension of String:

extension String {
    func capitalizingFirstLetter() -> String {
        return prefix(1).capitalized + dropFirst()
    }

    mutating func capitalizeFirstLetter() {
        self = self.capitalizingFirstLetter()
    }
}

Here’s an example to try it out:

let test = "the rain in Spain"
print(test.capitalizingFirstLetter())

SPONSORED In-app subscriptions are a pain. The code can be hard to write, hard to test, and full of edge cases. RevenueCat makes it straightforward and reliable so you can get back to building your app.

Explore the docs

Sponsor Hacking with Swift and reach the world's largest Swift community!

Available from iOS 8.0

Similar solutions…

• How to capitalize words in a string using capitalized
• What calls the first async function?
• How to find the first matching element in an array
• How to find the index of the first matching array element
• What is the first responder?

About the Swift Knowledge Base

This is part of the Swift Knowledge Base, a free, searchable collection of solutions for common iOS questions.