Welcome to HCODX Online Compiler
Quick Start:
Ctrl+Enter Run code
Ctrl+S Save / Download
Ctrl+L Clear output
Select a language and start coding.
Compile and run Swift code online instantly with HCODX. Our free cloud-based Swift compiler supports real-time execution, standard input, syntax highlighting, and code download. No installation or configuration required. Start coding in Swift now.
Run Swift instantly without installing any IDEs or configuring environments. Our cloud-based Swift handles libraries, runtimes, and dependencies automatically so you can focus on writing code.
Whether you are studying algorithms in Swift, practicing data structures in Swift, or exploring functional programming, our tool provides real-time stdout/stderr feedback with interactive standard input support.
HCODX is a free online compiler and code runner: write code in your browser, execute it on a cloud sandbox, and interact with your program through a live terminal. Students use it for coursework and interview practice; developers use it to test snippets in 85+ languages without setting up a local environment.
Swift is how modern iPhone, iPad, Mac, and Apple Watch apps get built — Apple introduced it in 2014 as a safe, fast successor to Objective-C, and companies like Uber, Lyft, and Airbnb write their iOS apps in it. Less well known: Swift is fully open source and runs on Linux, which is exactly how it executes here — a Swift toolchain compiles your file and runs it in an interactive terminal where readLine() waits for typed input. With Swift 6 adding compile-time data-race safety to its concurrency story, this page is a convenient way to practice optionals, closures, and protocols without owning a Mac.
print("Enter your name: ", terminator: "")
let name = readLine() ?? "friend"
print("Enter scores separated by spaces: ", terminator: "")
let scores = (readLine() ?? "")
.split(separator: " ")
.compactMap { Int($0) }
let total = scores.reduce(0, +)
print("Nice to meet you, \(name)!")
print("You entered \(scores.count) scores totaling \(total).")
if let best = scores.max() {
print("Best score: \(best)")
} else {
print("No valid scores found.")
}Learn Swift before you can afford the Mac — students on Windows or Chromebook laptops can complete the language portion of an iOS course entirely in this sandbox, then transfer to Xcode later. iOS interview prep leans heavily on language questions (optionals and unwrapping, value versus reference semantics, closures capturing self), all of which are testable here as plain console programs. It's also handy for isolating an algorithm from a SwiftUI app to debug it without simulator rebuilds. HCODX is a free online Swift editor, runner and interpreter — an IDE-grade compiler and playground to write and run code online, execute code with live output and live preview, no downloads or web server required.
Yes — your program runs attached to a live terminal, so each readLine() call suspends execution until you type a line. Note that readLine() returns an optional String?, which makes it a nice built-in exercise in optional handling: our example uses the ?? operator to supply a default.
No — UIKit and SwiftUI require Apple platforms and a rendering environment, and this sandbox runs Swift on Linux as a console program. Everything at the language level works: structs, enums with associated values, protocols and extensions, generics, closures, and error handling — which is precisely the layer most courses and interviews test.
Swift on Linux ships with the open-source Foundation implementation alongside the standard library, so types commonly seen in tutorials — String APIs, Date, and formatting helpers — are generally usable. A few Foundation corners behave differently on Linux than on macOS, so platform-specific behavior is worth verifying locally before shipping.
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