CodePen
Online code playground for HTML, CSS, and JavaScript with live preview and community sharing, ideal for prototyping and debugging frontend ideas.
CodePen offers live preview, preprocessor support (SCSS, TypeScript, Babel), and embeddable pens for documentation. The community challenges and "Picked Pens" curation surface creative frontend work daily.
Great for frontend developers prototyping animations, CSS layouts, and UI components. Also widely used for sharing reproducible bug reports, teaching web concepts, and embedding interactive examples in blog posts.
URL
https://codepen.io/Recommended tools
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