Code Runner

LoopLab App

Contains adsIn-app purchases

About this app

CodeRunner turns your phone into a real coding environment. Write code, hit run, and see real output in seconds — no setup, no terminal, no laptop required.

Whether you're learning to code, practicing for interviews, testing a quick idea, or just experimenting on the go, CodeRunner runs real code in 8 popular languages and shows you exactly what it outputs.

▶ RUN REAL CODE
Execute Python 3, JavaScript (Node), C, C++, Java, C#, Go, and Rust. Your code runs on real compilers and interpreters — not a simulation — so the output matches what you'd get on a desktop.

⌨ A REAL CODE EDITOR
Syntax highlighting, smart indentation, and a clean editor built for mobile. Switch languages instantly while keeping a separate buffer for each one, so you never lose your work.

📤 SEE THE OUTPUT
Get clear program output, including errors and runtime messages, right below your code. Perfect for debugging and understanding exactly how your program behaves.

💾 SAVE & REUSE SNIPPETS
Save your favorite code snippets and reuse them anytime. Your snippets sync automatically and work offline, so they're always with you across sessions.

✨ WHY CODERUNNER?
• 8 languages in one app
• Real execution with real output
• Fast, distraction-free mobile editor
• Save and organize reusable snippets
• Works offline for your saved code
• Clean, modern, easy-to-use interface

Great for:
• Students learning programming
• Developers testing quick ideas
• Interview and coding practice
• Anyone who wants to code without a computer

Download CodeRunner and start running real code from anywhere.

What’s new

Interactive input is here. Programs that read input now work the way you
expect: send a value in the console and CodeRunner runs your program with it.
Python, Java and C# read it line by line. C, C++, Go and Rust never pause for
input, so each value re-runs your program from the top. Either way, only the
first run counts against your free runs.

Also in this release: the paywall now states your real free-run allowance,
plus layout and stability fixes.