Web and HTTP Debugging and Troubleshooting Made Simple
Uncover software bugs when HTTP communication is involved. The Fiddler set of tools helps you promptly identify errors to effectively fix them. Easily.
Fiddler: One Product Family, Multiple Debugging Tools
Fiddler is a web debugging proxy tool for Windows, macOS and Linux. It has evolved from Fiddler Classic into a more robust and versatile product - Fiddler Everywhere. Fiddler Everywhere is now the only HTTPS debugger version in active development and with dedicated support, and a powerful tool for developers and QA professionals that offers:
Multiple options for capturing, including from remote device
Support for multiple protocols
Extensive Rules for modifying traffic
Advanced filters for narrowing down traffic
Offline mode
SOC 2 certification, and a lot more
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
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
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
Glossary
- Network DebuggingNetwork 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 CapturingThe 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.
- BugAn error, flaw, or fault in a software program that causes it to produce incorrect or unexpected results or behave unexpectedly.
- LoggingThe 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.
- BreakpointA marker set in the code where the execution will pause, allowing developers to inspect the state of the application at that specific point.
- HTTP/HTTPSThe 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/ResponseThe 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.
- CookiesSmall 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.