Skip to content
SPECIFICTION
Get listed

ILSpy

github.com

Free plan WindowsmacOSLinuxBrowser extension
Visit github.com
Spec score 7.6 #27 of 73 in Reverse Engineering Tools

What it is

ILSpy is free, open-source software for browsing and decompiling .NET assemblies on Windows, Linux, and macOS. Its Avalonia desktop interface converts assemblies to C#, including whole-project decompilation. Assemblies can come from disk, NuGet, running processes, or the Global Assembly Cache, although GAC support is limited to Windows. Search covers types, methods, and properties, with hyperlinks, bookmarks, base and derived type navigation, and an assembly metadata explorer. The application also includes BAML-to-XAML decompilation and support for ReadyToRun binaries for .NET Core. Related tooling includes Visual Studio 2022/2026 support, Visual Studio Code extensions, the ilspycmd dotnet tool, PowerShell cmdlets, and NuGet packages. Desktop plugins and a scripting API extend its use. ILSpy supports bytecode decompilation but not native-code decompilation. The project says it does not collect personally identifiable information, send user files to third-party services, or use application performance monitoring for telemetry. Release 11.1 is listed as the latest version, under the MIT License.

Spec sheet

Purpose
ILSpy is an open-source, cross-platform .NET assembly browser and decompiler.Read 4 Oct 2026 · github.com
Integrations
Frontends and related tools include Visual Studio 2022/2026 support, Visual Studio Code extensions, the ilspycmd dotnet tool, PowerShell cmdlets, and NuGet packages.Read 4 Oct 2026 · github.com
Privacy
ILSpy says it does not collect personally identifiable information, send user files to third-party services, or use an application performance monitoring service to collect telemetry or metrics.Read 4 Oct 2026 · github.com
Additional formats
ILSpy includes a BAML-to-XAML decompiler and support for ReadyToRun binaries for .NET Core.Read 4 Oct 2026 · github.com
Assembly sources
It can open assemblies from disk, the NuGet feed, running processes, and the GAC, with GAC support limited to Windows.Read 4 Oct 2026 · github.com
C# decompilation
ILSpy decompiles assemblies to C# and supports whole-project decompilation.Read 4 Oct 2026 · github.com
Desktop platforms
The desktop UI runs on Windows, Linux, and macOS and is built on Avalonia.Read 4 Oct 2026 · github.com
Extensibility
The desktop application can be extended with plugins.Read 4 Oct 2026 · github.com
Navigation and metadata
Features include searching types, methods, and properties; hyperlink navigation; bookmarks; base and derived type navigation; and an assembly metadata explorer.Read 4 Oct 2026 · github.com
Release
The GitHub releases page lists ILSpy 11.1 as the latest release.Read 4 Oct 2026 · github.com
Security reporting
The project asks that suspected security issues be reported privately by email and says it cannot guarantee a response time, though it strives to respond within one business day.Read 4 Oct 2026 · github.com
Supported versions
The security policy supports the latest released version and the latest preview or release-candidate version.Read 4 Oct 2026 · github.com

Plans and prices

ILSpy Free Open-source software · MIT License Read 4 Oct 2026 · github.com

Every ILSpy plan and price →

Strong points and limits

Strong points

  • Free MIT-licensed open-source software
  • Runs on Windows, Linux, and macOS
  • Whole-project C# decompilation
  • BAML-to-XAML and ReadyToRun support
  • Plugin and scripting API support

Limits

  • Does not decompile native code
  • GAC support is limited to Windows
  • No free trial is offered

Who it suits

It suits developers inspecting .NET assemblies, including users who need C# or whole-project decompilation. Its desktop, editor, command-line, PowerShell, and NuGet integrations support varied development setups.

Verdict

ILSpy provides broad .NET inspection and decompilation features across desktop and developer-tool integrations at no cost. Its main boundary is support for managed bytecode rather than native code, with GAC access restricted on non-Windows systems.

Where Specifiction places it

Alternatives to ILSpyAll alternatives →

JEB From $100/mo · Free plan 9.0 Visit