What is FiddlerCore

FiddlerCore is a .NET Class library you can integrate into your .NET Framework and Mono Framework applications. FiddlerCore allows you to capture and modify HTTP and HTTPS traffic just like Fiddler, without any of the Fiddler UI.


Key Features

  • HTTP and HTTPS traffic capture and modification.
  • Powerful object model for content filtering and modification.
  • Store and reload web traffic.
  • Support for virtually any client application.
  • Support for most devices via mobile proxy settings.


Why FiddlerCore

  • Battle-tested code used by millions of users of the Fiddler application.
  • Flexible licensing schemes for internal and public distribution.
  • Ongoing support from the core development team.

Version 4.4.9.8, released December 16, 2014

Download the documentation to learn how to develop with FiddlerCore. The install package contains .NET 2.0, 3.5, & 4.0 versions. A FiddlerCore.dll compiled targeting the Mono Framework is now in Alpha.

Please contact fiddler@telerik.com for commercial licensing questions.

Diagram showing Fiddler vs. FiddlerCore

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