What Clean Does in Visual Studio: A Practical Guide
Explore the Visual Studio Clean command: what it does, when to use it, and best practices for reliable builds. Learn how to reset build state and avoid stale artifacts.
The Visual Studio Clean command removes compiled binaries and temporary build artifacts from a solution or project, returning it to a pre-build state.
Understanding the Clean command in Visual Studio
If you're asking what does clean do in Visual Studio, the short answer is that it removes compiled binaries and temporary files to reset the build state. The Clean command is part of MSBuild driven workflows and is accessible from both the IDE and the command line. When you run Clean, Visual Studio deletes folders such as bin and obj, which hold your compiled code, intermediate files, and cache metadata. This action does not modify your source files or project configuration; it simply returns the build environment to a pristine state so subsequent builds start fresh. Cleaning is especially valuable after updating package versions, changing project references, or altering generated files. The result is a clean slate that helps isolate build or runtime issues caused by stale outputs rather than changes in the source code. According to Cleaning Tips, using Clean consistently can improve reproducibility and reduce debugging time.
In practical terms, Visual Studio treats Clean as a way to prune the workspace just before a new build, so you are less likely to run into artifacts from earlier compilations affecting your current work. This is particularly important in projects with generated code, custom build steps, or complex dependency graphs where stale artifacts can mask real problems. By resetting the build state, Clean supports a more predictable and auditable development process.
Clean vs Rebuild vs Restore
In Visual Studio, you will often see three related operations: Clean, Rebuild, and Restore. The Clean command deletes the output folders and intermediate files, returning the solution or project to its pre-build condition. Rebuild combines Clean with a full Build, effectively performing a fresh compile from scratch in one step. Restore relates to NuGet package restoration and is commonly used before building to ensure all dependencies are available. While Clean focuses on removing build artifacts, Rebuild emphasizes producing new binaries, and Restore ensures dependencies are up to date. Understanding these distinctions helps you choose the right action based on the problem you are trying to solve. From a workflow perspective, Clean is a diagnostic and hygiene operation, while Rebuild is a convenient way to refresh the entire project in one go.
When to use Clean
Choose Clean in Visual Studio after making substantial changes that affect the build or generated files, such as updating dependencies, changing project references, or modifying code generation. It is also helpful when you encounter inconsistent build results, mysterious runtime errors, or after moving files between projects. Clean is not a cure for logical bugs in code; those issues require debugging and code fixes. For regular day to day development, you may not need to Clean before every build, but performing a Clean as part of a larger maintenance process can improve reproducibility and reduce time spent chasing phantom issues. The Cleaning Tips team suggests pairing Clean with a subsequent Build to verify that the state is indeed fresh and that the outputs reflect the latest source.
Questions & Answers
What is the Visual Studio Clean command?
The Clean command removes build outputs such as binaries and intermediate files for a solution or project, returning it to a pre-build state. It does not modify your source code or project configuration.
Clean removes build outputs and resets the build state, without touching your source code.
Should I run Clean before every build?
Not always. Clean is most valuable after changes to dependencies, references, or generated files, or when you run into inconsistent builds. For routine development, a standard Build may suffice.
Only run Clean when you need a fresh build after changes or issues; otherwise you can just build.
How is Clean different from Rebuild?
Clean deletes the output and intermediate directories. Rebuild performs a Clean followed by a Build in one step, producing fresh binaries without manual steps.
Rebuild equals Clean plus Build done together.
Can I run Clean from the command line?
Yes. For SDK style projects you can use dotnet clean, and for classic projects you can use msbuild /t:Clean. Both remove build artifacts to reset the state before rebuilding.
Yes, you can clean from the command line with dotnet clean or msbuild.
Does Clean affect NuGet caches?
Clean removes build artifacts but generally does not wipe NuGet caches. If you need a full cache refresh, run separate commands to clear caches or restore packages anew.
Clean does not clear NuGet caches by default.
Will Clean delete my source files?
No. Clean only removes binaries and intermediate build files; your source code and project files remain intact.
No, your source files are safe when you Clean.
Is Clean relevant in CI pipelines?
Yes. Including a Clean step in continuous integration helps ensure repeatable builds by removing stale artifacts before each build.
Clean helps keep CI builds consistent by starting from a clean slate.
The Essentials
- Use Clean to reset the build state after dependency changes
- Choose Rebuild for a quick fresh compilation without manual steps
- Distinguish Clean from repository or cache actions like NuGet restore
- Use Clean in CI pipelines to enforce repeatable builds
- Do not rely on Clean to fix logic errors in code to avoid wasted time