Fiddler Tutorials & Guides

Learn how to set and use breakpoints in Fiddler to intercept and edit HTTP(S) requests before they leave your machine — essential for API testing and security validation.

A hands-on Fiddler tutorial covering manual, AutoResponder, FiddlerScript, and Composer techniques for editing HTTP request bodies — with HTTPS decryption tips and troubleshooting.

Learn how to mock 404, 500, timeouts & TLS errors in Fiddler for realistic HTTP debugging. Step-by-step AutoResponder and FiddlerScript techniques included.

Step-by-step guide to configure Fiddler Classic as your Windows system proxy for full HTTP debugging, including HTTPS decryption, exclusions, and troubleshooting.

Boost Fiddler’s speed for high-volume HTTP debugging: optimize inspectors, filters, HTTPS decryption, memory use, and automation — essential for professional fiddler proxy workflows.

Learn how to integrate FiddlerCore into CI/CD pipelines for automated HTTP debugging, HTTPS decryption, and reliable network visibility — with working examples for GitHub Actions, Azure Pipelines, and Jenkins.

Learn how to capture, inspect, modify, and troubleshoot WebSocket APIs using Fiddler — with HTTPS decryption, frame filtering, and scripting tips.

Master PowerShell-driven Fiddler automation for HTTP debugging, HTTPS decryption, session filtering, AutoResponder scripting, and CI integration.

Learn how to redirect URLs in Fiddler using AutoResponder — with HTTPS decryption, wildcards, regex, and real-world debugging examples.

Stuck with Fiddler not capturing traffic, HTTPS decryption failing, or crashes? Fix 6 common Fiddler errors with step-by-step solutions for HTTP debugging and fiddler proxy setup.