Fiddler Tutorials & Guides

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.

Learn how to use Fiddler Composer to build, send, and debug custom HTTP requests — with headers, JSON bodies, auth tokens, multipart uploads, and HTTPS decryption support.

Master Fiddler sessions and inspectors to decode HTTP(S) traffic, debug APIs, and validate security headers — a practical guide for developers and testers.

Master Fiddler's Statistics tab: decode HTTP timing, size, compression, and protocol metrics for real-world performance analysis and debugging.