The best free IDE alternative to CodePen is Replit. If that doesn't suit you, our users have ranked more than 50 alternatives to CodePen and 11 are free IDEs so hopefully you can find a suitable replacement. Other interesting free IDE alternatives to CodePen are Firebase Studio, Qoder IDE, kodeWeave and goormIDE.
Replit is a collaborative cloud development environment offering in-browser IDE features like AI assistance, real-time collaboration, Git support, hosting, deployment, syntax highlighting, plugin extensibility, ad-free UI, dark mode, and live code sharing.
A cloud-based, agentic development environment designed to accelerate how you build, test, deploy and run production-quality AI applications, all in one place.
Qoder is an AI-powered agentic coding platform and IDE that automates complex software development tasks using autonomous AI agents.
kodeWeave is a realtime coding playground for HTML, CSS and Javascript. Similar to JSFiddle and JSBin, but kodeWeave was made to work offline but also as a prototyping application to build applications for desktop operating systems while on mobile devices.
goormIDE is a powerful cloud IDE service to maximize the productivity for developers and teams. You can build your own development environment with just a few clicks and collaborate in real-time on the same docker container.
Storm is an online web development environment which allows users to run HTML, CSS, Javascript code in real time in a secured environment. It supports sharing Scribble (Storm project) via a dedicated link and also allows users to use jQuery and React framework of JavaScript.
Codiad is an open source, web-based, cloud IDE and code editor with minimal footprint and requirements
Atheos is a web-based IDE framework with a small footprint and minimal requirements, built on top of Codiad by FluidByte and the Codiad Team.
A web-based IDE to teach programming in the classroom. Easily create and share exercises with students. Analyze and inspect students' submissions.
United States
China
South Korea
Ukraine
I like replit because they have a great free version with AI autocomplete and chat.