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CodeRunner - Secure Multi-Language Code Sandbox

CodeRunnerCode ExecutionOnline IDESandboxProgrammingPiston APIDevelopment Tools

Overview

CodeRunner Sandbox is a powerful, cloud-based environment for writing, executing, and testing code directly in the browser. Available through the CodeSpark ecosystem, this tool eliminates the need for local setups, IDE installations, or compiler configuration. Whether you're learning a new programming language, testing logic, experimenting with algorithms, or running quick prototypes, CodeRunner provides a seamless, secure, and high-performance experience.

Accessible at CodeSpark → Code Runner Sandbox, this platform supports multiple languages, real-time execution, isolated sandboxes, and a clean, distraction-free interface. Built with modern developers in mind, it leverages the robust Piston API to deliver secure and rate-limited code execution across environments.

Core Philosophy and Design Principles

CodeRunner is designed around three foundational principles:

1. Learn & Build Without Setup

No installation, no environment configuration, no compilers — everything runs directly in the browser. This makes CodeRunner ideal for:

  • Students learning programming
  • Interview preparation
  • Quick debugging
  • API testing
  • Algorithm prototyping

2. Security at the Core

Every code execution runs inside an isolated sandbox environment.
Your code:

  • Cannot access system-level files
  • Cannot harm other processes
  • Cannot escape the sandbox
  • Is rate-limited for safety

3. Multi-Language, Multi-Platform

CodeRunner supports a variety of popular programming languages including:

  • Python
  • JavaScript (Node.js)
  • C
  • C++
  • Java
  • Go
  • Rust
  • And more (via auto-detection)

It works on any device — desktops, tablets, Chromebooks, or mobile devices.

Key Features

Multi-Language Support

Execute programs in multiple languages with instant interpretation or compilation.
Ideal for learners and developers switching between languages.

Real-Time Execution

Code runs instantly, with results streamed back into the terminal in real-time.
This simulates a modern IDE’s interactive output experience.

Cross-Platform Compatibility

Since everything is web-based, you can:

  • Write code on a laptop
  • Test logic on your phone
  • Run scripts on a tablet
  • Continue work anywhere

Secure Sandbox Environment

The platform ensures:

  • Isolated code execution
  • No access to system commands
  • Protection from malicious inputs
  • Safe environment for student learning

Pre-Configured Inputs

Provide input in advance using the Program Input Panel, useful for:

  • Testing interactive code
  • Providing multiple test cases
  • Competitive programming workflows
  • Simulating user input

Auto-Detection of Language

The editor intelligently detects the language of your code when possible, saving valuable setup time.

How to Use CodeRunner

Getting started is simple and takes less than a minute.

Step 1: Write Your Code

Enter your program in the editor. Choose your language or let auto-detection handle it.

Step 2: Add Inputs (Optional)

Insert inputs into the Pre-configured Input Box: