When comparing Brackets vs Eclipse, the Slant community recommends Brackets for most people. In the question“What are the best IDEs for web development?” Brackets is ranked 7th while Eclipse is ranked 16th. The most important reason people chose Brackets is:
Brackets will automatically refresh the browser and load the latest saved version of a file open in the browser. This works with php as well. Editing a css will even highlight the tag that's currently being worked on. However, it only works with Chrome.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Built-in browser live-updating
Brackets will automatically refresh the browser and load the latest saved version of a file open in the browser. This works with php as well. Editing a css will even highlight the tag that's currently being worked on. However, it only works with Chrome.
Pro Lightweight
Brackets is easy on memory usage and it starts up quickly.
Pro Free, open source and cross-platform
Brackets is entirely free and open source.
Pro Built-in extension manager
The functionality of Brackets can be extended via a simple-to-use extension manager. The extension manager also has a considerable number of extensions and themes.
Pro Can style a tag without switching over to the stylesheet
A feature called "Quick Edit" allows the user to select a tag in (a html file, for example) and edit the associated style without switching over to the css document. It also supports SASS and LESS pre-processors.
Pro Actively developed
Brackets is being actively maintained and developed.
Pro Popup previews
Hovering over colors hex codes or image paths will pop up previews of corresponding colors and images.
Pro Drag and drop support
Brackets supports drag and drop of text, as well as multi / rectangular selection.

Pro Can be hacked by any front-end developer
The editor is built using html, css, and javascript, making it extendable by any front-end developer.
Pro Multi-line (multi-query) editing
You can have your cursor independently on multiple lines and so creating templates and/or editing multiple things at once is really fast and easy.
Pro Vim mode
Vim-style editing is already built in the text editor.

Pro Support for Adobe PSD content
A default extension allows for the extraction of PSD resources, such as images and styles. There's good integration for placing extracted resources into source.
Pro Free and open source
Eclipse is an open source project and free to use.
Pro Multiple languages - one IDE
Pro Large selection of plugins
Eclipse has a large and active community, which has resulted in a wide variety of plugins.
Pro Fast compiler
Eclipse uses a custom compiler (which can also be used outside of Eclipse), which is often faster than the normal Java Compiler, especially for incremental compilation.
Pro Easy to use and get started with
It's interface is super easy to use, after adding required package for your task everything just works.
Pro Gives good perspectives on your project
The concept of perspectives is outstanding. It puts right tools at your fingertips, keeping the tools you currently don't need out from the workbench. For example, in VCS perspective it's all about versions and branches. In debug perspective it's all about state.
In java ee project it can show http endpoints in a very accessible manner.
Pro Highly customizable
Thanks to the large variety of plugins and various configuration options, Eclipse is very customizable.
Pro Great debugger
Shows threads, concurrency locks, and conditional breakpoints.
Pro Good font rendering
Because Eclipse is based on SWT, it uses the native font rendering and thus looks better than other IDEs on some Linux systems, where the Java font rendering is not optimal.
Pro Good refactoring tools
Pro Faster than any other Java IDE
Fast, suitable for big projects, customizable, supports UML, many programming languages, plugins, and widgets vs NetBeans and JDeveloper. Support for Workspaces and Perspectives. Long term tested, free of charge, vs IntelliJ IDEA.
Pro Great in-UI documentation
Pro Dark theme improved!
Cons
Con Still missing some elementary text editor commands
Some gaps have to be filled by plugins, while these features should be built in.
For example:
- Jump to matching brace (bracket / parenthesis);
- Gutter selection of lines;
- Recall previous searches / replacements;
- Autofill of search field with text under caret (text has to be selected);
- Show whitespace / end of lines / indentation guides / right margin;
- Selection to upper / lower case;
and some more.
Con Problematic updater
Though the website says there is an update available, the updater in Brackets may give you an error, resulting in you having to download updates manually.

Con Slow
Con Supports only web languages by default <but>
Brackets is built for web development and that's where it excels at out of the box. Other languages that have a CodeMirror mode can be added as well.
<and language support plugins can be added>
Con Branding & online website is super cluttered
There are lots of official home pages for this IDE, the packages, and the repos - hard to find correct one. Also, the main name in IDE: "Eclipse", is same as "Eclipse Foundation" which makes things more confusing.
Con UI can be confusing
There's an overly abundant presence of menus, this forces you to constantly click around the different menu structures; foreign ideas, like Views and Perspectives; strange menu choices, like configure settings located in Windows menu->Preferences.
Con Lack of plugins with good user interfaces
Many Eclipse plugins are extremely confusing, with UIs that are even less consistent than Eclipse itself.
Con Plugins can be unstable
Though there are plenty of plugins to choose from, they aren't always reliable. Some aren't maintained, bug fixes can be slow, and you may need to download plugins from multiple sources.
Con Tends to be slow and lags a lot
Con Poor language support via plugins
Eclipse supports other languages with a huge amount of plugins. Many languages have their own distribution, but multi-language is hard to exist in one project. Like Scala, there is no official support from Eclipse for this language. If Eclipse gets an update, languages such as these will not.
Con Newer versions are getting less stable
Eclipse 4 Neon randomly hangs. For example, during installing new software.
https://bugs.eclipse.org/bugs/show_bug.cgi?id=513218
Con Some old bugs don't get fixed
E.g. change a parameter name to the same as a field - the field will not be prefixed with "this." like in IDEA.
