CodePen vs OneCompiler

CodePen is a web-based social development environment for creating, testing, deploying, sharing and discovering front-end code. In a Pen, users write HTML, CSS and JavaScript and see a live browser preview. It supports HTML preprocessors such as Markdown, Haml, Slim and Pug, and CSS preprocessors including Sass, Less, Stylus and PostCSS. The CodePen 2.0 editor supports automatic preprocessing, live previews, file systems, version history, collaboration and one-click Pen deployment. Users can add external CSS and JavaScript resources, reuse other Pens, find libraries through CDNjs and import bare npm packages through its compiler. Pens can be embedded on other websites, and CodePen documents a REST API and other embed and prefill options. Pens and Projects are public by default. PRO users can make Pens and Collections private, but anyone with the shared URL can view them without logging in. The free plan includes unlimited public Pens and three files per Pen. Starter costs $8 a month, Developer $12 a month and Super $26 a month. CodePen does not offer a self-hosted version.

OneCompiler is an online environment for writing, running and sharing code, available on the web and Android. It supports more than 60 programming languages, plus web technologies and databases such as MySQL, MongoDB and PostgreSQL. Its free plan includes unlimited code executions and 20 AI credits per day. OneCompiler Studio runs Visual Studio Code in a browser with a Linux container, terminal, package manager, debugger and persistent workspaces; supported projects can be deployed to a live URL and shared by link. The service also offers code execution APIs and embeddable editor, challenge, Studio and AI interview capabilities. Its LMS integration uses a JWT token and requires an email address and name to create or sign in a user. OneCompiler supports private projects, real-time collaboration, public sharing and custom domains. The company says it helps over 12.8 million developers worldwide and describes use by LLM companies, colleges, EdTech providers and interview companies. Organizations are being retired; new ones cannot be created and no further features are planned for them.