Open-source alternative to Fiddler
Telerik Fiddler is a robust web debugging tool that allows users to monitor, manipulate, and replay HTTP/HTTPS traffic. It provides a wide range of features, including performance testing, web session manipulation, and security testing, making it a comprehensive solution for web development and debugging.
On the other hand, Requestly is an open source tool available as both browser extension and desktop app. It allows users to set up rules for modifying URLs, injecting scripts, and redirecting requests. It provides a broad range of functionalities, including the ability to manipulate both request and response data, making it a versatile tool for front-end developers.
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Comparing Requestly vs Fiddler
Requestly is a light-weight & open-source alternative to Fiddler that is available as both Browser extension & Desktop app.
Modify HTTP Headers & Responses
A complete HTTP debugging software that works on your browser, simple & fast.
Modify API Response
Develop frontend without ready a backend or Modify existing API responses on production environment
Modify HTTP Headers
Add, Delete or Override Request & Response Headers
Redirect API and script requests
Redirect APIs/Scripts from one environment to another (e.g. Prod to Staging)
Insert Custom Scripts
Inject custom scripts/styles on external webpages for testing/demo purposes.
Simple & Secure API client for Front-end Developers
A comprehensive and web-based tool for modifying and testing APIs.
Import cURL Requests
Import your cURL requests easily from other API platforms
Send API Requests And Test Responses
You can customize request headers, query parameters, and request body payloads to test different scenarios.
History of API requests
Find the History of API Requests you made to debug them easily.
Frequently Asked Questions
Ready to get started?
The tool enables you to inspect incoming and outgoing data to monitor and modify requests and responses before the browser receives them.
No, Fiddler has a free trial, after that you have to pay for the product.
No, Fiddler is not a open source tool.
Fiddler everywhere cost $10 per month per user.
Fiddler is a web-debugging proxy that monitors, inspects, edits, and logs all HTTP(S) traffic and issue requests between your computer and the Internet.