Apps similar to Firefox Developer Tools include Google Chrome Developer Tools, which is free and open source. Other options are Web Developer, HTTP Debugger, Try It Online (TIO) and DOMScope. You can choose from more than 10 Web Debuggers like Firefox Developer Tools for Windows, Linux, Mac, the web and self-hosting.
The Google Chrome Developer Tools provide an integrated environment for debugging, optimizing, and understanding a web application, or website, running in Google Chrome. The developer tools are developed partly through the WebKit open source project, where the tools are called...
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The Web Developer extension adds various web developer tools to a browser. The extension is available for Chrome, Edge, Firefox, and Opera, and will run on any platform that these browsers support including Windows, macOS and Linux.
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HTTP Debugger captures and decrypts HTTP/HTTPS from any Windows app without proxy setup — HTTP/2, WebSocket, SSE, gRPC and localhost included. Edit and replay requests, modify traffic on the fly, and let an AI assistant read the session over the built-in MCP server.
TIO is a family of online interpreters for an evergrowing list of practical and recreational programming languages.
DOMScope is an online web inspector and debugger for mobile web apps. Like Chrome's DevTools, it allows developers to navigate through the HTML, list applied CSS styles and execute JavaScript code inside any device's browser.
Plunker is an online community for creating, collaborating on and sharing your web development ideas.
HttpFox monitors and analyzes all incoming and outgoing HTTP traffic between the browser and the web servers.
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HttpWatch is an HTTP viewer and debugger that integrates with IE and Firefox to provide seamless HTTP and HTTPS monitoring without leaving the browser window. It's available as a free edition and a PRO version that cost money and has additional features.
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Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.
TinyJSD is a JavaScript debugger for privileged code running Mozilla products like Firefox, Thunderbird, SeaMonkey. It serves to debug the application as well as extensions written in JavsScript.
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Compile and Execute your favorite programming languages online, click any of the following to proceed! Web Technologies, Text Formatting, Useful Utilities, Programming Languages. Vim, emacs modes are avaliable.
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