DotPeek Tool: A .NET Decompiler


The dotPeek decompiler tool was initially introduced by Microsoft. It’s a free-of-charge, standalone tool-based decompiler for any .NET assemblies. It converts .NET assemblies into equivalent C# code and optionally shows the underlying IL code. A dotPeek application can decompile different kinds of assembly files, such as Libraries (.dll), Executable files (.exe), Windows 8 metadata files (.winmd), Archives (.zip), NuGet packages (.nupkg), and Microsoft Visual Studio Extensions packages (.vsix).

Developers can use dotPeek to decompile .NET assemblies based on .NET Framework 1.0 to 4.5 into the equivalent C# code.

Features of .NET Decompiler

Following is the list of features developers can explore.

View Source Code if Available

DotPeek can generate PDB files. Decompiled code generated by dotPeek can be used to match an assembly to its source code. This tool allows developers to download code from a remote server location, as shown in Figure 1.

Navigation and decompiler options
Figure 1: Navigation and decompiler options

Show or Hide Compiler-generated Code

As a developer, we may want to show or hide the compiler-generated code created by this .NET decompiler. We may choose to show certain compiler transformations, thus making a code structure that dotPeek displays. This feature helps to see how the compiler deals with lambdas, closures, and auto-properties, among other things.

Explore Running Processes

The Process Explorer window of the tool shows the list of all currently running processes. A developer can explore these modules and decompile all the .NET assemblies. A developer can choose to show or hide native processes and modules, or turn on process hierarchy view. You also can filter the list to find a module or process that you’re looking for (see Figure 2).

Process Explorer
Figure 2: Process Explorer

View IL Code in a Separate View

A developer can navigate to IL code from any point of decompiled C# code. That feature is required to dive deeper inside source code. The dotPeek tool provides an easy way to show IL code in a separate tool window that is synchronized with the main code viewer.

View IL Code as Comments to Decompiled C#

A developer also can opt to show IL code as comments to decompiled C# code. DotPeek can display IL code both for decompiled code and for source code reproduced from symbol files.

Preferred Color Theme

DotPeek supports a number of color themes, such as the Visual Studio editor. Developers can select a Blue or Dark theme, or choose to synchronize your color scheme preference with Visual Studio settings.

How to Use Symbols

From dotPeek, you can find all usages of a symbol (such as a method or property) across all loaded assemblies. The usages will be displayed in the Find Results tool window where you can group them, navigate between them, and open in the code view area.

There’s also Find Usages Advanced, which is a more detailed version of Find Usages that helps you fine-tune search criteria by limiting the scope of search and other details.

Highlight Usages in a Code Viewer

DotPeek automatically highlights all visible usages of the symbol under a caret, very similarly to how recent versions of Visual Studio do it. This helps improve the readability of decompiled code.

Jump to Any Code

DotPeek provides two features to quickly jump to specific code:

  • Go to Symbol: Helps navigate to a specific symbol declaration, which could be a type, method, field, or property.
  • Go to Everything: Allows searching for an assembly, namespace, type, member, or a recently opened file.


To go back to specific lines of decompiled code later, feel free to set bookmarks.

You can create up to 10 numbered bookmarks, and unlimited unnumbered bookmarks. The full list of bookmarked locations is displayed in a single pop-up window.


DotPeek supports Navigate contextually and by class hierarchies. Go to Declaration takes you from a usage of any symbol to its declaration. Go to Implementation helps navigate to end implementations of types and type members, bypassing intermediate inheritance steps in the inheritance chain.

Explore Inheritance Chains

DotPeek will show you all types that are inherited from the selected type, as well as types that it inherits themselves.

Manage Assembly Lists

A developer can work with different assembly lists, depending on context. You can save and re-open assembly lists, and clear the current list if you no longer need it.

Explore Assembly Contents

The Assembly Explorer shows what kind of references, resources, and code a particular assembly has, all the way from namespaces to type members.

Explore Assembly Metadata

DotPeek helps you explore assembly metadata and dig through all items (tables, blobs, strings, and so forth) inside it. Under the Metadata node, you can explore values of blob items, PE file headers, and usages of metadata table items.


I hope this article about dotPeek has given you basic understanding of its usage. To know more, visit this URL.

More by Author

Must Read