WEBJX collects very useful free JavaScript development tools

Whether you're a new JavaScript novice or a seasoned developer, the tools you use directly affect your productivity. The open source movement makes it less expensive to have a powerful tool, and you don't actually have to pay for anything. Here's a list of free tools that really have practical value for JavaScript developers.

Test

Validator for Jslint–javascript

JSLint gets a JavaScript source code and scans it. If a problem is found, it sends back information describing the problem status and the approximate location in the source code. The problem is not necessarily syntactic, but it is often a mistake here. JSLint look at some style conventions and structural issues, and it doesn't prove that the program is correct. It just provides another pair of eyes to help find the problem.

JsUnit

Jsunit is a client (internal browser) JavaScript Unit test framework. It's actually a port for JUnit to JavaScript. There is also a platform for automating test execution on multiple browsers and on multiple machines running different operating systems.

YUI Test

YUI test is a test framework for browser-based JavaScript solutions. You can use Yui test to easily add unit tests on JavaScript solutions.

obtrusive JavaScript Checker

can be used as Firefox extensions, Greasemonkey user scripts, and ubiquity commands; obtrusive JavaScript Checker is a tool that can sweep through all the elements on a page and discover HTML elements with inline events (this is dangerous , JavaScript is supposed to be unassuming), it gives this part a red edge to make it stand out.

Crosscheck

Crosscheck is an open source test framework that validates the JavaScript code within the browser. It helps you make sure that your code runs on a variety of browsers, such as Internet Explorer and Firefox, that don't need to be installed.

Jslitmus

Jslitmus is a lightweight tool used to make JavaScript-specific standard tests.

Test plugin for JAVASCRIPTMVC

JAVASCRIPTMVC's Test library provides event simulations, unit tests, Ajax fixtures, and a console program.

Debugging

JavaScript Debugging Kit

The JavaScript Debugging Toolkit is an eclipse plugin that is debugging JavaScript across browsers, and it can debug JavaScript on Ie,firefox,safari,chrome,opera and even mobile browsers.

Firebug

As the most popular web Developer tool, Firebug is a Firefox plugin that can be used to edit, debug and monitor CSS, HTML, and JavaScript on any page. It provides JavaScript login and debug consoles with some useful features such as AJAX requests Logging,javascript interpreter, DOM Explorer, and so on.

Firebug Lite can be used on IE, Opera, and Safari.

Venkman

Venkman provides a powerful JavaScript debugging environment for gecko based browsers. This debugger is used in the form of Firefox & Mozilla Plug-ins. You can use breakpoint management in the user interface and console commands, call stack checking, variable/object checking, and so on, allowing you to adjust in the most customary way.

Nitobibug

Nitobibug is a browser-based JavaScript object recording and checking tool-similar to the Firebug function. Nitobibug can be run on a variety of servers (ie6+, Safari, Opera, Firefox) to provide a consistent and powerful tool for developing AJAX applications.

Damnit

Damnit is a free service that sends you e-mail when a user encounters a JavaScript error on a Web page.

JS Bin

JS bin is an online Web application designed specifically to help JavaScript developers test snippets and collaborate on debugging code in certain scenarios. You can use JS bin to edit and test JavaScript and HTML code online. Once completed, you can save the URL and send it to your partner for review or help.

Blackbird

Many JavaScript developers simply use alert () to display a variety of information debugging code. Blackbird provides a simple way to record information on JavaScript and a compelling console program to view and filter information.

HTTP Monitoring

Fiddler

Fiddler is a Web debugging agent that records all of the HTTP (S) traffic between your computer and your network. You can use Fiddler to check all HTTP (S) traffic, set breakpoints, and interfere in or out of data.

Tamperdata

Tamperdata is a Firefox extension that tracks and modifies HTTP/HTTPS requests. It can be used as a security test for web-based applications to track requests/responses.

Live HTTP Headers

You can view the HTTP headers of your Web page while browsing. You can debug a Web application with live HTTP headers, find out which Web server the remote site is using, or view small data files sent by the remote site.

File

Jgrousedoc

Jgrousedoc can generate API files from annotations in the source code. You can use this tool to document all the constructs you need-not only functions and variables, but also class packages, interfaces, namespaces, packages, and more. Using that JavaScript framework is irrelevant-you can record code in the way you want without a frame or tool imposed

JSDoc Toolkit

A file generator of JavaScript, written in JavaScript, that automatically generates format templates from the raised JavaScript source code, multiple page HTML (or XML, JSON, or other text).

Compression

Online Javascript Compression Tool

An online JavaScript compressor that can compress JavaScript files with some compression algorithms such as jsmin and Packer . Compressed JavaScript files are ideal for production environments because they often reduce file size 30-90%. To a large extent, the size of the file is reduced by removing comments and extra whitespace characters that are not needed by web browsers or visitors.

Scriptalizer

An online tool that combines multiple JavaScript files into one file.

Dojo Shrinksafe

A command-line utility that allows you to reduce the size of a file by using a browser, thereby shortening the response time. Dojo compressors are not based on fragile regular expressions. It is based on a JavaScript engine from the Meuse project. Because a real parse Stream,dojo compressor is better than a rule-based expression tool to represent the environment of DAIFU (variable name, etc.).

YUI Compressor

The YUI compressor is a JavaScript compression device. In addition to removing annotations and spaces, it can also confuse local variables with the smallest available variable names. This confusion is also safe, even when using constructs such as ' eval ' or ' with ' (in which compression is not appropriate). Compared with jsmin, it saves an average of 20%.

Formatting

JavaScript Code Landscaping Tools

This landscaping tool handles scattered or compressed JavaScript code, and continues to format it quickly and make it readable.

Editing Programs & Integrated development environment

Aptana Studio

Aptana Studio is a complete network development environment. It provides automated JavaScript code completion and debugging, Html/css/javascript code hints, and support for important Ajax class libraries. Aptana Studio even provides code hints for all of your pages, including your own JavaScript.

Komodo Edit

Komodo Edit is a free and open source editing program. It provides automatic completion, call prompts, multiple language support, syntax highlighting color display, grammar checking, Vi emulation,emacs Accelerator binding, and so on. Extended Komodo Edit is one of its most useful features. You'll find various extensions useful to JavaScript developers (such as JSLint plugin for Komodo,venkman JavaScript Debugger, and so on).

Spket IDE

The Spket IDE is a powerful toolkit for JavaScript and XML development. JavaScript, XUL/XBL and Yahoo! Widgets develop powerful editors. The JavaScript editor has features such as code completion, syntax highlighting, and content profiling that help developers efficiently create effective JavaScript code. The Spket IDE is available free of charge for non-commercial use.

Other tools

Google's AJAX APIs playground

AJAX API playground loaded with Google JavaScript APIs (Maps, Search, Feeds, Calendar, visualization, Language, Blogger, libraries and E Arth, etc.) example, you can edit these examples to help you explore the functionality that Google's APIs can provide. There are also save and output functions. You can use the Save function to keep the edited example to be used later. The output function can be used to modify the example and publish the code on a permanent URL.

Compatibility Table of quirksmode–

Check out the most popular sources for CSS2, CSS3, Dom Core, Dom HTML, Dom CSS, Dom Events, and CSS Object Model view's main browser compatibility state.

HTML to JavaScript converters

The HTML to JavaScript converter gets the markup and converts it into a series of document.write () declarations that can be used in JavaScript blocks.

Glimmer

Glimmer is a desktop application that lets you easily make interactive elements on a Web page using the jquery Library's role. You can use it to easily create interlaced sensations such as rotating albums/headers, drop-down navigation, hover effects, or custom animations.

JQuery Function Builder

You can use this tool to quickly create a set of functions that call the set of functions when the page is finished loading/ready.

JavaScript Regex Generator

An online tool for making regular representations.

Other browser extensions

Firefox, Flock & SeaMonkey Network Developer Extensions

Web developers have added a menu and toolbar to the browser that includes many web development tools including the ability to make your XHTML work, discover JAVASCRIPT/CSS errors, Web page structure visualization, test Web Forms, change the XHTML in the run, check HTTP header information, and more.

Opera Dragonfly

Opera Dragonfly is a cross device of opera browser, cross-platform debugging environment-debugging JavaScript, checking the editing of CSS and DOM, and viewing errors on mobile devices or computers.

IE6/7 's developer tool bar

Microsoft's Internet Explorer Developer toolbar provides a variety of tools for the rapid creation, understanding, and troubleshooting of Web pages.

Original:List of Really useful free Tools for JavaScript developers