CodePen

Free online tool — no sign-up required

CodePen is a browser-based HTML, CSS, and JavaScript playground where developers can write, test, and share front-end code instantly. Create "pens" to prototype ideas, explore community creations, and learn from millions of examples. Perfect for experimenting with new CSS techniques, JavaScript libraries, and web animations.

This tool is interactive — turn on JavaScript to use it.

How to Use CodePen

  1. Visit CodePen — Go to codepen.io — start coding immediately or create a free account to save work.
  2. Create a new Pen — Click New Pen to get HTML, CSS, and JS editors with live preview.
  3. Write and preview — Code in real-time and see results instantly in the preview pane.
  4. Add libraries — Include external CSS/JS libraries like React, Vue, or Bootstrap with one click.
  5. Share your work — Share your Pen via URL, embed it in blog posts, or explore community creations.

CodePen — Frequently Asked Questions

Is CodePen free?

Yes, the free plan lets you create unlimited public pens. Pro plans add private pens and extra features.

What languages does it support?

HTML, CSS, JavaScript, and preprocessors like Sass, LESS, TypeScript, Pug, and more.

Can I use frameworks like React?

Yes, you can include React, Vue, Angular, and other libraries via CDN or npm.

Can I embed pens on my website?

Yes, CodePen provides embed codes to include your pens in blog posts and websites.

Is it good for learning?

Absolutely! Browse millions of community pens to learn techniques, fork examples, and experiment.

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