Online C# Compiler
main
// Online C# compiler to run .NET code in the browser.
// Write C# code in this online editor — no install needed.
using System;
class Greeter {
public void Greet() {
Console.WriteLine("Hello, Tutorsbot!");
}
}
class Program {
static void Main() {
var g = new Greeter();
g.Greet();
}
}
C# is Microsoft's flagship language powering .NET, ASP.NET, and Unity game development. Run C# code online — ideal for OOP patterns and .NET interview prep.
Free Online C# Compiler — Mono in Your Browser
Run C# online without installing Visual Studio, .NET SDK, or Rider. This playground executes C# on the Mono runtime in a sandboxed cloud environment, so you can prototype a LINQ query, test an async method, rehearse a data-structures interview question, or share a runnable example with a teammate — all without setting up a toolchain. The editor uses the same professional code editor used by millions of developers, so IntelliSense matches your local experience.
C# Playground for .NET Developers
Common use cases: prototype a LINQ pipeline (`Where`, `Select`, `GroupBy`) before adding it to production code, test async/await exception handling against a real async API, rehearse a data-structures question in front of an interview panel, or run a snippet from a book without standing up a solution file. The compiler reports both Mono compile errors and the runtime output. For a guided path beyond playground experimentation, see Tutorsbot's C#/.NET Training and ASP.NET Training programmes.
Which C# Features Are Supported?
C# on Mono supports most language features: records, pattern matching (`is` patterns, `switch` expressions), nullable reference types, top-level statements, file-scoped namespaces, `with` expressions, init-only setters, target-typed `new`, and async streams. The standard library is available: `System.Collections.Generic`, `System.Linq`, `System.IO`, `System.Text`, `System.Text.Json`, `System.Threading.Tasks`. .NET Framework APIs that depend on Windows (WPF, WinForms) are not available — this playground targets the cross-platform BCL.
Is the Online C# Compiler Free?
Yes — 100% free for evaluation, learning, and interview preparation. No account, no captcha, no per-day limit. For production features (multi-file projects, NuGet packages, persistent repls, scheduled jobs), see Tutorsbot's C#/.NET Training or enterprise plans.
What the Online C# Compiler Supports
This compiler runs with the modern .NET base class library: `System.Linq`, `System.Collections.Generic`, `System.Text.Json`, `System.IO`, `System.Threading.Tasks`, `System.Net.Http`, `System.Text.RegularExpressions`, plus the entire `System.Console` family. Top-level statements, records, pattern matching, `init`-only setters, nullable reference types (when you opt in via `enable ` in your snippet), and `using` directives all work. What is NOT supported: ASP.NET Core, WPF, WinForms, MAUI, anything that needs a database driver, and NuGet packages — the sandbox does not resolve external dependencies. Multi-file projects are not supported; concatenate into a single file.
Why use the C# online compiler?
- C# — supports LINQ, async/await, generics, pattern matching
- Standard library: System.Collections, System.IO, System.Linq, System.Text
- Compile errors with line/column mapping in the Output panel
- Persistent workspace with autosave to localStorage
Frequently Asked Questions
- Is the C# online compiler free?
- Yes — Tutorsbot's C# compiler is completely free. No account required, no installation, and no usage limits.
- Do I need to install C#?
- No. The C# compiler runs entirely in your browser. No runtime, no SDK, no PATH configuration. Open the page and start coding.
- Is my C# code saved between sessions?
- Yes — your code autosaves to your browser's local storage so you can resume where you left off. You can also generate a shareable URL.
- Can I share C# code with others?
- Yes. Click the Share button to copy a URL that encodes your script. Anyone with the link can open and run it instantly — no account required on their end.
- Is the C# compiler safe to use?
- Absolutely. Every program runs in an isolated sandbox. Your local system is never exposed to the executed code, and nothing is persisted after the execution window.