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Fiddler Everywhere is our most popular solution for modern web debugging, or choose the Fiddler product that's right for you. Choose Your Fiddler Capture Traffic on Your Machine with Fiddler Everywhere Get Network Logs from Your Customers' Machines with Fiddler Reporter Integrate Network Capturing into Your Application with FiddlerCore Fiddler Everywhere is our recommended solution for modern web debugging, licensed for professional and commercial use. It delivers advanced debugging features, dedicated support, and cross-platform traffic inspection for Windows, macOS, and Linux. Need Fiddler Classic instead? Fiddler Classic remains available for eligible non-commercial use under the updated EULA. Multiple options for capturing, including from remote device and offline mode Support for multiple protocols Extensive Rules for modifying traffic Advanced filters for narrowing down traffic AI-assisted debugging with Fiddler MCP Enterprise-ready, including SOC 2 certification Try for Free Learn more Looking for Fiddler Classic? Download it here for eligible non-commercial use. Fiddler Everywhere Reporter is a free cross-platform traffic capture tool which allows you to: Start instantly without installation, perfect for restricted-permission environments Skip registration or licensing, ensuring a faster and hassle-free setup Capture data easily even as a non-technical user Receive web traffic from end users or internal teams for debugging Try for Free Windows - Portable App Windows - Zip Intel Mac ARM Mac Learn more FiddlerCore is an embeddable .NET library which enables you to: Integrate traffic capture capabilities directly into your code Monitor and analyze traffic within your application Gain deep insights and superior performance analysis Discover delays, missing services and threats in minutes not days Try for Free Learn more How to Start Your Fiddler Journey 1 Try the Fiddler product(s) and the web debugger that aligns with your needs. 2 Integrate Fiddler into your workflow for rapid, elegant debugging and troubleshooting. 3 You’ll start realizing the high value of benefits of Fiddler through the acceleration of both your time and cost savings. Hundreds of Thousands of Organizations are Using Fiddler Join these companies and the 4 million developers who are already building, running, and debugging with Fiddler proxy tools. 4.4 Out of 5 Overall User Rating Don’t just take our word for it. G2 Users have consistently rated Fiddler 4.4 out of 5 stars. G2 is a renowned peer-to-peer review site that aggregates user reviews for business software. Support & Learning Blog How to Select the Right Fiddler Tool for You Resource Fiddler Everywhere – Licensing and Purchasing FAQs Resource Fiddler Everywhere - Getting Started Contact us How Can We Help? We'd Love to Hear from You! Glossary Network Debugging Network debugging is the process of identifying and resolving issues in web applications by inspecting and modifying HTTP/S traffic between a client, usually a web browser, and a server. It involves using tools to intercept, analyze, and manipulate web requests and responses, allowing developers to troubleshoot problems, optimize performance, and ensure security and functionality. Common tasks in web debugging include examining network traffic, checking for errors in code, and testing how the application behaves under different conditions. Fiddler Everywhere is a powerful web debugging proxy to facilitate your debugging efforts and optimize your processes. Network Capturing The process of intercepting, recording, and analyzing data packets as they travel across a network, allowing developers and QA professionals to monitor the communication between devices, identify issues, diagnose problems, and ensure the security and performance of networked applications. Bug An error, flaw, or fault in a software program that causes it to produce incorrect or unexpected results or behave unexpectedly.  Logging The process of recording detailed information about the application's execution, often used to track events, errors, and data flow, which helps in identifying issues during debugging.  Breakpoint A marker set in the code where the execution will pause, allowing developers to inspect the state of the application at that specific point.  HTTP/HTTPS The main protocols for web communication, where HTTP (Hypertext Transfer Protocol) and HTTPS (HTTP Secure) are used to send and receive data between a client and a server.  Request/Response The basic communication model in web debugging, where a client sends a request to the server, and the server returns a response. Analyzing these helps identifying issues.  Cookies Small pieces of data used to track user activity that the web server generates and sends to a web browser, which stores the cookies for a predetermined period of time. Debugging often involves inspecting cookies to ensure they are set, sent, and received correctly.  A Trial of Any of the Fiddler Products Gives You:​​ A fully functional version of the software. Strict data privacy protection. Your data remains with you, it will never be shared.​ Easy upgrade path to a licensed product. Full access to all online documentation, community forums and tutorials. 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