March 06, 2025 • 3 min read

Online Compiler

Demo/Repo
Online Compiler

Building an Online Compiler with React and Piston API

Introduction

In the world of programming, having a reliable online compiler can significantly enhance productivity. Whether you're testing quick snippets or working on small projects, an online compiler eliminates the need to set up multiple environments. This blog explores an online compiler built using React, Piston API, and Context API, allowing users to compile code in over 45 programming languages with advanced features like IntelliSense and syntax highlighting.

Features

1. Multi-Language Support

This online compiler supports over 45 programming languages, making it versatile for developers working with different technologies. From Python and JavaScript to C++, Rust, and Go, you can execute your code seamlessly without needing additional installations.

2. Theme Customization

Users can personalize their coding experience with 40 different themes, including popular VS Code themes. Whether you prefer a dark mode for night coding or a high-contrast theme for better visibility, there’s a theme for every preference.

3. Resizable Editor Layout

The interface is divided into three resizable panes, allowing a structured and flexible coding environment:

  • Left Pane – The code editor, where users write and edit their code.
  • Top Right Pane – A dedicated input area for providing custom input to the program.
  • Bottom Right Pane – Displays the output after executing the code.

4. IntelliSense & Syntax Highlighting

The compiler provides real-time IntelliSense suggestions and syntax highlighting, enhancing the overall coding experience and reducing errors.

How It Works

1. Writing and Compiling Code

Users write their code in the editor and provide any necessary input in the input pane. The system ensures that syntax is highlighted correctly based on the selected programming language.

2. API Integration

The execution process is powered by the Piston API, which takes the code and input as parameters and returns the compiled output. The request contains:

  • The programming language selected.
  • The source code written by the user.
  • Any additional input required for execution.

3. Fetching and Displaying Results

Once the API processes the request, the compiled output is displayed in the output pane, allowing users to see the results in real time.

Conclusion

This online compiler provides an efficient and customizable environment for coding directly in the browser. With multi-language support, IntelliSense, syntax highlighting, and customizable themes, it serves as a powerful tool for both beginners and experienced developers. Whether you’re testing small code snippets or learning a new language, this online compiler enhances the coding experience by making it seamless and hassle-free.

Try it out and experience a smooth, web-based coding journey!