Fiddler Tutorials & Guides

Step-by-step guide to install Fiddler Classic and Fiddler Everywhere on Windows 11 in 2026 — including HTTPS decryption, firewall config, and troubleshooting.

Master API endpoint testing with Fiddler Composer: step-by-step guide covering HTTPS decryption, auth headers, multipart forms, and real-world debugging for developers and QA engineers.

Learn how to establish reliable HTTP(S) performance baselines and compare before/after changes using Fiddler’s inspectors, timings, and SAZ analysis tools.

Learn how to debug OAuth 2.0 authorization code, PKCE, and token flows in real time using Fiddler’s HTTPS decryption, filtering, and scripting features.

A hands-on fiddler tutorial for intercepting, inspecting, and testing mobile app APIs — covering HTTPS decryption, Android/iOS setup, and real-time request tampering.

Learn how Fiddler sessions and inspectors work—step-by-step guidance on filtering, HTTPS decryption, timing analysis, and request manipulation for effective HTTP debugging.

Learn how to debug OAuth 2.0 flows end-to-end using Fiddler: HTTPS decryption, JWT inspection, PKCE validation, and request replay for API testing.

Master advanced Fiddler automation with PowerShell: connect via COM, filter sessions, export HAR/SAZ, enforce HTTPS decryption, and build reusable debugging workflows.

Fiddler slowing down your internet? Discover 6 proven fixes — from disabling HTTPS decryption to optimizing filters and UI settings — for faster HTTP debugging and smoother fiddler proxy performance.

Learn how to identify HTTP performance bottlenecks using Fiddler’s waterfall chart, HTTPS decryption, custom rules, and statistics. A hands-on fiddler tutorial for developers and testers.