The free web debugging proxy for any browser, system or platform.
Debug traffic from PC, Mac or Linux systems and mobile devices. Ensure the proper cookies, headers and cache directives are transferred between the client and server. Supports any framework, including .NET, Java, Ruby, etc.
Fiddler lets you see the «total page weight,» HTTP caching and compression at a glance. Isolate performance bottlenecks with rules like «Flag any uncompressed responses larger than 25kb.»
Fiddler is a free web debugging proxy which logs all HTTP(s) traffic between your computer and the Internet. Use it to debug traffic from virtually any application that supports a proxy like IE, Chrome, Safari, Firefox, Opera and more.
Easily manipulate and edit web sessions. All you need to do is set a breakpoint to pause the processing of the session and permit alteration of the request/response. You can also compose your own HTTP requests to run through Fiddler.
Use Fiddler for security testing your web applications — decrypt HTTPS traffic, and display and modify requests using a man-in-the-middle decryption technique. Configure Fiddler to decrypt all traffic, or only specific sessions.
Benefit from a rich extensibility model, ranging from simple FiddlerScript to powerful Extensions which can be developed using any .NET language.
The Fiddler Server is the machine on which Fiddler is installed. Some scenarios may require specific steps for Fiddler to receive and send web traffic. This includes:
- Types of traffic, like decrypting HTTPS and authenticating with channel-binding tokens
- Operating systems, like Windows 8 and Mac OSX
- Network configurations, like monitoring a remote machine, chaining to an upstream proxy, using Fiddler as a Reverse Proxy, monitoring local traffic or monitoring dial-up and VPN connections
The client is the source of the web traffic that Fiddler monitors. Some client applications, operating systems, and devices may require specific steps to send and receive traffic to and from Fiddler. This includes:
- Browsers, like Firefox, Opera, or IE (when sending traffic to localhost)
- Applications, like .NET apps, WinHTTP Apps, Java Apps, and PHP/cURL apps
- Devices, like Android, iOS, Windows Phone 7, and PocketPC devices