Whistle - free open source alternatives of Charles, Fiddler

App Name	Whistle
Price	Free
Rating
Platform	WindowsmacOSLinuxAndroidiOS
Website	Visit Whistle website
Source code/Download	Get Whistle
Logo	Preview
App Preview	Preview
Introduction	HTTP, HTTP2, HTTPS, Websocket debugging proxy.
Plans	Free Plan Free & open source.

Whistle is a free open source alternative to following apps:

Charles

HTTP proxy / HTTP monitor / Reverse Proxy that enables a developer to view all of the HTTP and SSL / HTTPS traffic between their machine and the Internet.

Fiddler

Amplify your debugging efforts with a Web Debugging Proxy for any device or platform. Fiddler Everywhere is a pathway for all, supporting macOS, Linux and Windows.