CodePen is a social development environment for front-end designers and developers. 👋 It’s the best place to build and deploy a website, show off your work, build test cases, and find inspiration. We call them Pens.
Repl.it is a complete, collaborative cloud development environment in the browser featuring everything from linters and debuggers to third-party packages, hosting and deployment. FEATURES - Real-time collaborative code editing. - Live chat in the workspace.