Run Code in Your Browser: Best Online Compilers for C++, PHP, Python, Java, C#, Go & More

Online compilers are tools that let you write, compile, and run code directly in your browser—no installation needed. While full-fledged IDEs provide advanced debugging and project management tools, they can also be bulky and slow. If your goal is quick code execution, then browser-based environments are more than enough.

I’ve handpicked the best online compilers for popular languages like C++, Python, PHP, Java, Go, and even more niche options.

🔁 Best Multi-Language Online Compilers

Online IDE

• ✅ Autocomplete suggestions as you type
• ✅ Multi-file support and local file import
• ✅ Terminal with argument inputs
• ✅ Dark mode and no registration required
• ✅ Share or download code easily

A great all-around tool when you want speed, structure, and clarity in your code.

Ideone

• ✅ Supports popular and obscure languages (e.g., Assembly, Fortran)
• ✅ Three visibility modes: public, secret (link-only), and private
• ✅ Registered users get extended execution time (15s vs. 5s)

Ideal for quick code snippets and sharing small demos.

Replit

• ✅ Full project structure support with directories and Git integration
• ✅ Built-in debugger, environment variables, database integration
• ✅ Team collaboration and live coding sessions
• ✅ Free version includes most features; Pro unlocks faster builds and private repos

Replit is one of the closest experiences to a full desktop IDE—right in your browser.

CodingGround

• ✅ Simple editor with over 70 supported languages
• ✅ One-file execution—perfect for quick checks
• ✅ Integrated with TutorialsPoint’s learning ecosystem

Great for learners and quick validation.

OneCompiler

• ✅ 40+ languages, SQL dialects, and frontend frameworks
• ✅ Input support for programs
• ✅ Integrated tutorials and practice problems for all levels

Perfect for both coding and skill-building.

GeeksforGeeks Online IDE

• ✅ Popular language support with optional input file loading
• ✅ Autocomplete, shortcut keys, and mobile-friendly UI
• ✅ Tied to an educational platform with free and premium content

Perfect for students and tech interview prep.

W3Schools Editor

• ✅ Supports languages taught on W3Schools: C++, C#, PHP, Python, Go, JavaScript, and more
• ✅ Minimalist UI—just code and run
• ✅ Includes HTML, CSS, and SQL editors

A simple tool for learners, with zero overhead.

💻 C, C++ Online Compiler

OnlineGDB

• ✅ Built specifically for C and C++
• ✅ Multiple file support and integrated debugger
• ✅ Code beautifier for auto-formatting

One of the best free platforms if you're writing C/C++ frequently.

🔷 C# Online Compiler

DotNetFiddle

• ✅ Supports C#, F#, and VB.NET
• ✅ Shareable code snippets and collaborative editing
• ✅ Modes for Console, Script, MVC, and Nancy frameworks
• ✅ “Tidy Up” feature to auto-format your code

Perfect for testing .NET concepts on the go.

🌐 Online Compilers for Web Development

CodeSandbox

• ✅ Extensive support for frontend tech like React, Vue.js, Node.js
• ✅ GitHub integration, deployment options
• ✅ Public by default, private in paid plan

Ideal for quick frontend prototyping or sharing live web projects.

🚀 Go Online Compiler

The Go Playground (Official)

• ✅ Simple editor with input/output
• ✅ Best for small Go snippets
• ✅ Limited functionality compared to full IDEs

Use for lightweight testing or quick algorithm checks. For more features, try Replit or OnlineGDB.

☕ Java Online Compiler

JDoodle

• ✅ Choose language version, add command-line args
• ✅ Collaborate live (great for interviews)
• ✅ Two modes for Java: basic and advanced
• ✅ Import dependencies from Maven Repository

JDoodle is especially Java-friendly with features tailored for enterprise use.

Online compilers are incredibly useful whether you're a student practicing code, a developer debugging a snippet, or a hobbyist experimenting with ideas. Many of them now support collaboration, debugging, version control, and even deployment—features that were once limited to desktop IDEs.