Is there a good in-browser code editor? [closed]

CodeMirror comes with support for 60+ languages, and addons that implement more advanced editing functionality (autocompletion, code folding, configurable key bindings, search & replace, linter integration etc.). A rich programming API and a CSS theming system are available for customizing CodeMirror, and extending it with new functionality.

It has been developed since early 2007, has a Wikipedia page, and is being used in a wide number of popular open source projects (Joomla, Firebug etc.).


Ace. They don't use an iFrame.


The editArea javascript library does a pretty good job. It's used by the OpenCMS content management system as it's in-place JSP and JavaScript editor. The colorization gets a bit confused when the file is > 2000 lines or so.

The feature list from their page is:

  • Easy to integrate, only one script include and one function call
  • Tab support (allow to write well formated source code)
  • Search and replace (with regexp)
  • Customizable real-time syntax highlighting (currently: PHP, CSS, Javascript, Python, HTML, XML, VB, C, CPP, SQL, Pascal, Basic, Brainf*ck)
  • Auto-indenting new lines
  • Line numbering
  • Multilanguage support (currently: Croatian, Danish, English, French, German, Italian, Japanese, Polish, Portuguese)
  • Full screen mode
  • Can work in the same environment than "protype" and "mootools"'s like libraries.

Mozilla's Bespin looked very interesting, but the project was discontinued.


you can check out dockPHP StackHive for web development (based on codemirror). Right now it supports HTML/CSS development but I am working on live javascript-ing as well..

Disclaimer : I am the founder at dockPHP :)