Online Swift Compiler

Write and run Swift code directly in your browser with this free online compiler. Swift is Apple's modern programming language for iOS, macOS, watchOS, and tvOS app development. It is designed to be safe, fast, and expressive. This compiler lets you learn and test Swift code instantly without a Mac or Xcode.

What is Swift?

Swift is a general-purpose programming language developed by Apple and released in 2014. It was designed to replace Objective-C for Apple platform development while being safer, faster, and more modern. Swift features type inference, optionals for null safety, protocol-oriented programming, and closures. It compiles to native machine code using LLVM and also supports an interactive REPL for rapid prototyping. Swift has grown beyond Apple platforms and is used for server-side development with Vapor.

Key Features

• Type Inference: The compiler automatically deduces variable types.
• Optionals: Safe handling of missing values at compile time.
• Protocol-Oriented: Build flexible architectures using protocols.
• Memory Safety: Automatic reference counting prevents memory leaks.
• Modern Syntax: Clean, expressive code with powerful string interpolation.

Basic Swift Syntax

// Struct definition
struct Developer {
    let name: String

    func greet() {
        print("Welcome, \(name)!")
    }
}

// Enum
enum Language {
    case swift, python, java
}

func main() {
    // Variables
    let site = "LabsICT"
    let year = 2025

    // Array and loop
    let languages = ["Swift", "Python", "Java"]
    for lang in languages {
        print("Learn \(lang) at \(site)")
    }

    // Struct usage
    let dev = Developer(name: "Bilal")
    dev.greet()

    // Optional
    let optionalValue: String? = nil
    let value = optionalValue ?? "Default"
    print(value)
}

main()

What Can You Build with Swift?

Swift is the primary language for building iOS, macOS, watchOS, and tvOS applications. Companies like Apple, LinkedIn, Airbnb, and Slack use Swift for their mobile apps. Server-side Swift with Vapor enables building full-stack web applications. Swift is also used for command-line tools, machine learning with Core ML, and augmented reality apps with ARKit. Its safety features and modern syntax make it excellent for learning programming.

Try It Yourself

Type your Swift code in the editor and click Run. The compiler supports Swift features including structs, enums, optionals, closures, and protocol extensions. Use Copy to save, Reset to restore the example, and Share to generate a link.

Related Resources

Continue with our Swift learning track, try more online compilers, or browse tutorials for step-by-step guides.