When comparing ShiftEdit vs Codepen, the Slant community recommends ShiftEdit for most people. In the question“What are the best cloud IDEs?” ShiftEdit is ranked 5th while Codepen is ranked 22nd.
Ranked in these QuestionsQuestion Ranking
Pro Low cost, high quality
Pro Revision control
Pro Syntax checking
Highlights syntax errors and automatically fix some errors
Pro Supports multiple file access points
Access files from FTP, SFTP, WebDAV, Dropbox, Google Drive or Amazon S3
Pro Supports autocomplete
Code completion for HTML tags, CSS and PHP code assist
Pro SSH support
Allows connecting directly to a server and run commands on that server.
Pro Good Customer Support
Help requests get answered quickly and successfully.
Pro Easily export your pen
CodePen makes it really easy to export code as a zip or Github Gist.
Pro Real time output
Pro Lots of support for frameworks and preprocessors
CodePen has an impressive amount of support for preprocessors (such as Jade, Haml, Slim, Sass, Less, Stylus, Coffeescript and PostCSS). There is also plenty of frameworks and libraries to pick from (Foundation, Bootstrap, Angular, D3, Backbone, Ember etc.).
Pro Great display/profile page
The codepen profile page allows you to display all of your public pens, and control which order you want them to be viewed in. This is great for showing off your work to possible employers, other devs etc..
Pro Easily fork pens
To fork a pen only requires clicking one button, and you'll be able to modify the pen on your own account.
Pro Great community pens
You can search through other pens, either by keyword or popular, picked or recent.