Open Source Alternatives to Fiddler

A debugging proxy that captures and analyzes HTTP/HTTPS traffic for web and mobile applications, allowing developers to inspect, modify, and replay requests and responses.

Whether you want to cut software costs or escape vendor lock-in, these open source alternatives to Fiddler give you an option you fully own. They run locally on your own device, so your data never leaves your machine. This page lists 1 open source alternative to Fiddler. The most popular is Reqable.