C# online coding platform
Write and run C# in the cloud on a pre-configured .NET workspace.
Start coding free →C# in the cloud, ready in under a minute.
C# is a modern, statically typed, object-oriented language developed by Microsoft. It runs on the .NET platform and covers web apps, desktop apps, mobile, gaming, and IoT. On RunCode, you get a cloud workspace with the .NET runtime, VS Code in the browser, and a terminal ready in under a minute.
Open a C# workspace →What C# offers
C# is statically typed, meaning the compiler catches type errors before your code runs. It supports object-oriented patterns through classes, inheritance, polymorphism, and encapsulation. LINQ (Language Integrated Query) lets you query collections and databases using C# syntax rather than raw SQL. The language is closely tied to the .NET SDK, which ships libraries for networking, file I/O, JSON, HTTP clients, and more. C# is widely used in enterprise settings for web services, desktop software, and backend APIs, where compile-time checking reduces bugs over time.
- Static typing with compile-time error detection
- Full object-oriented support: inheritance, polymorphism, encapsulation
- LINQ for querying collections and databases in C# syntax
- .NET SDK libraries for networking, data access, and security
- Active ecosystem with NuGet packages for most tasks
What you get on RunCode for C#
- .NET runtime and SDK preinstalled
- dotnet CLI for building, testing, and running projects
- VS Code with C# extension in the browser
- Git support for GitHub, GitLab, and Bitbucket
- Workspace ready in under a minute
Need to run C# inside your own app?
OnlineCompiler.io, our code execution API, runs the C# your app sends it and returns the output, exit code, CPU time and memory. Each run gets a fresh sandbox, and the first 100,000 requests a month are free.