How easy is it to Decompile .NET apps?

All .NET applications and libraries are compiled to Microsoft Intermediate Language (MSIL). MSIL maintains high-level information about your code include its structure and class, field, method, property and parameter names. With a free decompiler, it is very easy to recreate the source code. Obfuscation and related techniques can make it much more difficult for a hacker or competitor to reverse-engineer your application.

Why use a .NET Obfuscator?

By making a .NET application much more difficult to reverse-engineer, you can help protect against intellectual property (trade secret) theft, bypassing licensing or other access checks, and searching for vulnerabilities.

How does Obfuscation and Code Protection Work?

Various different techniques that complement each other are used to create a layered defense to make reverse engineering, tampering, debugging much more difficult.

Some examples include:

  • Rename Obfuscation
  • String Encryption
  • Control Flow Obfuscation
  • Unused Code and Metadata Removal
  • Binary Linking/Merging
  • Dummy Code Insertion
  • Instruction Pattern Transformation
  • Opaque Predicate Insertion
  • Anti-Tamper Wrapping
  • Anti-Debug Wrapping
  • Watermarking
  • Security Alerts
  • Custom Response to Tamper or Debugging

Code Before and After Rename Obfuscation and String Encryption Only

Before .NET Obfuscation

.NET Code Before Obfuscation

After .NET Obfuscation

.NET Code After Baseline Obfuscation


Learn more about additional .NET Code Protection and Security features here.

Why should you protect your .NET code against debugging?

Whether a hacker is trying to steal your data, pirate your app, or modify the behavior of a critical piece of software as part of a larger crime – a production debugger is the hacker’s weapon of choice. You should not make it easy for them.

Protect and Secure your .NET Code

Dotfuscator is a .NET Obfuscator & much more. It provides enterprise-grade app protection, greatly reducing the risk of piracy, intellectual property theft and tampering. Our layered obfuscation, encryption, watermarking, auto-expiry, anti-debug, anti-tampering and alerting and defense technology provides protection for hundreds of thousands of applications around the world.

Why choose PreEmptive to Obfuscate, Secure and Protect your .NET Apps?

We’ve seen it all!

  • We protect and harden all .NET applications (mobile, server, desktop) while supporting highly-complex development and build environments.
  • We provide seamless integration with Visual Studio, as well as support for Xamarin and Universal Apps.
  • Incremental obfuscation facilitates releasing patches without redistribution of your entire application.
  • Cross-assembly obfuscation extends renaming and other advanced protection capabilities across multiple binaries and distributed development support.
  • Built-in “Smart” Obfuscation provides optimized support for XAML, BAML, XAP, mobile and ClickOnce scenarios.

Tried & True

  • Our .NET code protection is subjected to Microsoft regression tests, security audits, code reviews and quality gates as part of the Visual Studio development platform.
  • With an install-base estimated at over 1,000,000, you can be confident that almost every issue has been identified, diagnosed, and addressed.
  • We’ve been making sure your applications are protected for the last 20 years and we plan to be around for the next 100!

Support & Updates

  • Dotfuscator is continually being improved to keep ahead of malicious characters – we average six releases per year.
  • Our protection products are our main development focus and we are continually improving them based on our customers’ feedback.
  • We have a dedicated, experienced support team ready to help you.

Watch: Quick Demo of .NET Obfuscation and its effect on Reverse Engineering

This six minute video shows how easy it is to reverse engineer .NET code and demonstrates Dotfuscator's protection.

Techniques of Obfuscation

Learn about the technologies that make up obfuscation and application self protection.

Code Obfuscation Explained

Try it for free to find out for yourself!

Download the latest version of Dotfuscator to try it out! (Website registration required).

Try it!

Want to know more information?

The Dotfuscator - .NET Obfuscator features page explains how a layered .NET obfuscation approach can provide the protection you need.

Dotfuscator - .NET Obfuscator Features