Online C# Compiler & Algorithm Visualizer – Run C# Online (6, 7, 8)
Write, compile, and run C# code instantly in your browser. This free online C# compiler needs no installation or signup — just type your C# program, click Run, and see the output. Supports stdin, multi‑file projects, shareable snippet URLs, and AI help to generate, fix, and explain C# code.
About Online Compiler
Our free online compiler lets you write, compile, and run code instantly in your browser. Supports Python, Java, C++, JavaScript, Go, Rust, and many more languages. No installation required.
Compare Languages Side by Side
Want to see how Csharp stacks up against another language? Open the Code Playground to run Csharp next to Python, Go, Rust, or any language — each pane picks its own language and version, and you run them together.
Supported Languages
Popular: Python, Java, C++, C, JavaScript, TypeScript, Go, Rust
Web: PHP, Ruby, Node.js, HTML/CSS
Systems: C, C++, Rust, Go, Swift
Functional: Haskell, Scala, Kotlin, F#, Clojure
Features
- Monaco Editor (VS Code) with syntax highlighting
- Real-time code execution with output streaming
- Custom compiler flags support (-O2, -Wall, etc.)
- Share code via unique snippet URLs
- Keyboard shortcuts (Ctrl+Enter to run)
Run & Visualize C# Online (6, 7, 8)
Write and run C# online (language levels 6, 7, 8). Plus a built‑in algorithm visualizer: click Visualize to watch your code run line by line as int[], List, Dictionary, HashSet, Stack/Queue, 2D matrices, linked lists, and binary trees animate step by step — with a call‑stack view for recursion and thread swim lanes (lock hand‑off and deadlock detection) for concurrency. Ideal for learning sorting, binary search, recursion, BFS/DFS, hashing, and tree traversals. Multi‑file and shareable snippet URLs supported.
FAQ
Does the online C# compiler include an algorithm visualizer? Yes. Click Visualize to step through your code while arrays, lists, dictionaries, sets, stacks, queues, linked lists, and trees animate — a built‑in C# visualizer that highlights each read and write, the current line, and the call stack for recursion.
Which data structures and algorithms can I visualize? int[] and List<int>, 2D matrices (int[,] / int[][]), Dictionary, HashSet, Stack/Queue, and class‑based linked lists and binary trees — plus thread & lock concurrency shown as swim lanes with deadlock detection. Great for sorting, binary search, recursion, BFS/DFS, frequency counting, and BST traversals.
Which C# versions are supported? C# language levels 6, 7, and 8.
Multi‑file projects? Yes, add additional .cs files and a Main entry point.
How do I share code? Use Share to generate a link.
How to Use Online Compiler
Choose from 60+ programming languages including Python, Java, C++, JavaScript, Go, Rust, and more.
Use our Monaco editor (same as VS Code) with syntax highlighting, auto-completion, and error detection.
Click Run or press Ctrl+Enter. Your code executes in a secure sandbox and output appears instantly.
Share your code via unique URL or embed interactive code snippets in your blog, book, or documentation.
For Authors, Educators & Technical Writers
Perfect for programming books, online tutorials, technical documentation, and educational content. Embed interactive, runnable code examples directly in your content.
Click Embed button above to generate embed code for your content!
Example: Hello World in C#
using System;
class Program {
static void Main() {
Console.WriteLine("Hello, World!");
}
}Copy this C# snippet into the editor above and click Run to execute it instantly — no setup required.
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