Progress Telerik Fiddler Classic 5.0

Progress Telerik Fiddler Classic is a free Windows-based web debugging proxy from Progress Software Corporation. It captures, inspects, and modifies HTTP and HTTPS traffic between your applications and the internet, making it easier to troubleshoot web apps, APIs, and services across browsers, desktop apps, and even mobile devices configured to use the proxy.

Key capabilities:

• Comprehensive traffic capture and inspection, including headers, cookies, payloads (JSON, XML), and raw requests/responses
• HTTPS decryption with an opt-in, trusted root certificate for secure debugging
• Composer to craft, replay, and batch requests for rapid API testing
• AutoResponder to mock endpoints, serve local files, and simulate server behavior or outages
• Filters to focus on specific hosts, processes, methods, or content types
• Breakpoints and rules for tampering with requests/responses, plus connection throttling to simulate real-world network conditions
• Statistics and timeline views for performance and payload analysis
• Extensibility through FiddlerScript and add-ons to automate workflows and customize behavior

Fiddler Classic is well-suited for developers, QA engineers, and support teams diagnosing issues such as failed requests, authentication and redirect problems, caching behavior, and payload or header anomalies. Note: Fiddler Classic runs on Windows. For a cross‑platform option, Progress also offers Fiddler Everywhere.

Progress Telerik Fiddler Classic is developed by Progress Software Corporation. The most popular version of this product among our users is 5.0. The names of program executable files are anything (2).exe, Fiddler.exe and Piddler.exe.