---
aid: codepen
name: CodePen
description: >-
  CodePen is a social development environment for front-end designers and
  developers, offering a browser-based playground for writing and sharing
  HTML, CSS, and JavaScript. The platform allows users to create "Pens"
  (interactive code snippets) and share them publicly or privately. CodePen
  provides developer-facing APIs including an Embed API for displaying Pens
  on external sites, a POST to Prefill API for programmatically opening the
  Pen editor with pre-populated code, Prefill Embeds for transforming
  existing code blocks into interactive sandboxes, and an oEmbed endpoint
  for standard embed discovery. The platform is widely used by educators,
  tutorial authors, and documentation teams who need live, interactive
  code examples embedded in external pages.
type: Index
image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
tags:
  - Developer Tools
  - Front-End Development
  - Code Playground
  - Embeds
  - Education
url: https://raw.githubusercontent.com/api-evangelist/codepen/refs/heads/main/apis.yml
created: '2026-06-12'
modified: '2026-06-12'
specificationVersion: '0.19'
apis:
  - aid: codepen:oembed
    name: CodePen oEmbed API
    description: >-
      Standard oEmbed endpoint that returns a rich embed payload (iframe HTML,
      thumbnail URL, author metadata) for any public CodePen Pen URL. Supports
      JSON and JSONP response formats and an optional height parameter.
    humanURL: https://blog.codepen.io/documentation/oembed/
    baseURL: https://codepen.io/api/oembed
    tags:
      - oEmbed
      - Embeds
      - Front-End Development
    properties:
      - type: Documentation
        url: https://blog.codepen.io/documentation/oembed/

  - aid: codepen:embed
    name: CodePen Embed API
    description: >-
      Client-side JavaScript API for rendering and lazy-loading embedded Pens on
      external web pages. Uses the global window.__CPEmbed() function with
      data-* attributes on a .codepen div to control height, theme, default tab,
      animations, and zoom level. A __CodePenIFrameAddedToPage callback is
      available for post-embed hooks.
    humanURL: https://blog.codepen.io/documentation/embedded-pens/
    baseURL: https://public.codepenassets.com/embed/index.js
    tags:
      - Embeds
      - JavaScript
      - Front-End Development
    properties:
      - type: Documentation
        url: https://blog.codepen.io/documentation/embedded-pens/

  - aid: codepen:post-to-prefill
    name: CodePen POST to Prefill API
    description: >-
      HTTP POST endpoint that accepts JSON-encoded code and configuration and
      opens a new (unsaved) Pen in the CodePen editor pre-populated with that
      content. Supports HTML, CSS, and JS content fields, preprocessor choices,
      external resources, and editor layout. No authentication is required.
    humanURL: https://blog.codepen.io/documentation/prefill/
    baseURL: https://codepen.io/pen/define/
    tags:
      - Front-End Development
      - Developer Tools
    properties:
      - type: Documentation
        url: https://blog.codepen.io/documentation/prefill/

  - aid: codepen:prefill-embeds
    name: CodePen Prefill Embeds API
    description: >-
      Declarative embed API that transforms existing code blocks on a web page
      into live, interactive CodePen sandboxes without requiring users to
      navigate away. Code is supplied via data-prefill JSON attributes and
      pre elements; the embed script at public.codepenassets.com renders
      an isolated iFrame. Supports HTML, CSS, and JavaScript preprocessors,
      external stylesheets and scripts, and optional editable mode.
    humanURL: https://blog.codepen.io/documentation/prefill-embeds/
    baseURL: https://public.codepenassets.com/embed/index.js
    tags:
      - Embeds
      - Front-End Development
      - JavaScript
    properties:
      - type: Documentation
        url: https://blog.codepen.io/documentation/prefill-embeds/

common:
  - type: Website
    url: https://codepen.io
  - type: Documentation
    url: https://blog.codepen.io/documentation/
  - type: GitHubOrganization
    url: https://github.com/codepen
  - type: LinkedIn
    url: https://www.linkedin.com/company/codepen
  - type: Blog
    url: https://blog.codepen.io
  - type: Pricing
    url: https://codepen.io/pricing
  - type: X
    url: https://twitter.com/CodePen
  - type: Plans
    url: plans/codepen-plans-pricing.yml
  - type: RateLimits
    url: rate-limits/codepen-rate-limits.yml
  - type: FinOps
    url: finops/codepen-finops.yml
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com