Installing .NET and F#

F# doesn't require a separate installer — it has shipped as part of the .NET SDK since .NET Core 2.0, so installing .NET automatically gives you the F# compiler (fsc), the F# Interactive REPL (fsi), and MSBuild support for F# projects. Downloading the SDK from dotnet.microsoft.com (or your OS package manager) is the only prerequisite before writing your first .fs or .fsx file.

On Windows, the easiest path is winget install Microsoft.DotNet.SDK.8, or the graphical installer from the .NET site; on macOS, brew install dotnet-sdk; on most Linux distributions, apt install dotnet-sdk-8.0 (Ubuntu/Debian) or the equivalent for your package manager, since Microsoft publishes feeds for major distros. It's worth choosing a Long-Term Support (LTS) release, such as .NET 8, unless you specifically need preview features, since LTS versions get security patches for three years.

Once installed, F# Interactive (dotnet fsi) gives you a read-eval-print loop for experimenting with expressions line by line, which is invaluable while learning syntax before committing to a full project. For editing, Visual Studio Code with the Ionide-fsharp extension is the most popular free setup — it adds syntax highlighting, IntelliSense, and inline error checking powered by FSAutoComplete (FSAC); Visual Studio and JetBrains Rider both include F# tooling built in or via a lightweight plugin.

To verify the install, open a terminal and run dotnet --version to confirm the SDK is on your PATH, then create a throwaway project with dotnet new console -lang "F#" -o HelloFSharp and run it with dotnet run from inside that folder. If both commands succeed and you see printed output, your F# toolchain — compiler, runtime, and project templates — is fully working end to end.