For .NET Framework & .NET Standard

Telerik FiddlerCore The Power of Fiddler in Your App

.NET library that allows you to capture and modify
HTTP and HTTPS traffic.

Why FiddlerCore


Application/service troubleshooting

Debugging in production is always a challenge. With FiddlerCore Embedded Engine you can easily capture the application traffic and send it to your support and engineering team for further investigation. It’s the same as being on the client’s machine.

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Unit and performance testing

Building test gets harder in today’s API-first world. You can use FiddlerCore Embedded Engine to replace both your frontend and backend. Replicate your APIs without relying on a server. Modify the responses. Simulate different network conditions and user loads.

Ready to test?

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Network monitoring & analysis

Are you sure all your systems, devices and applications are running properly? You can use FiddlerCore Embedded Engine to monitor that everything on your network works smoothly and securely. Discover any delays, missing services or potential dangers in timely manner.

Ready to monitor?

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Key Features

  • Capture HTTP/HTTPS traffic

  • Import/export to various formats

  • Integration with Telerik Fiddler and Telerik TestStudio

  • Filter and modify traffic

  • Issue and modify responses

Browsium embraced FiddlerCore to build powerful browser management solutions. With hundreds of thousands of Browsium client installations worldwide, it has proven to be stable, reliable and efficient under a broad range of use and load scenarios. The Fiddler team is incredibly responsive, addressing issues and incorporating a solution that becomes a mainstream supported feature. Our teams also use Fiddler in customer application troubleshooting and creating customer configurations for their Browsium products.

Matt Heller Founder and Chairman

Support and Learning


Next Steps