Redoc

Redoc is an open-source tool developed by Redocly that automatically generates professional, interactive API documentation from OpenAPI (formerly Swagger) specification files. Optimized for readability and user experience, Redoc stands out with its modern three-column design, smooth navigation, and exceptional performance even for complex APIs with hundreds of endpoints.

Fundamentals

Automatic documentation generation from OpenAPI 2.0 and 3.x specifications
Three-column architecture: navigation, detailed description, and code examples
Client-side rendering with no server dependencies, entirely JavaScript/React-based
Integrated search, interactive table of contents, and synchronized scrolling between sections
Native support for custom themes and internationalization for global adoption

Benefits

Intuitive, professional user interface that improves API adoption by developers
Optimized performance through lazy-loading rendering, efficiently handling documentation of thousands of lines
Simplified deployment: a single HTML file hosted on CDN or static server suffices
Advanced customization via CSS themes, logos, brand colors, and SEO metadata
Native mobile compatibility and WCAG accessibility to reach all developer audiences
Open-source with active community and regular updates ensuring long-term viability

Practical Example

Here's how to integrate Redoc into a standalone HTML page to document your API:

api-docs.html

<!DOCTYPE html>
<html>
  <head>
    <title>API Documentation</title>
    <meta charset="utf-8"/>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link href="https://fonts.googleapis.com/css?family=Montserrat:300,400,700|Roboto:300,400,700" rel="stylesheet">
    <style>
      body {
        margin: 0;
        padding: 0;
      }
    </style>
  </head>
  <body>
    <redoc spec-url='https://api.example.com/openapi.json'
           hide-download-button
           theme='{
             "colors": {
               "primary": {"main": "#2563eb"}
             },
             "typography": {
               "fontSize": "16px",
               "headings": {"fontFamily": "Montserrat"}
             }
           }'></redoc>
    <script src="https://cdn.redoc.ly/redoc/latest/bundles/redoc.standalone.js"></script>
  </body>
</html>

For a more advanced React integration with state management:

ApiDocumentation.tsx

import { RedocStandalone } from 'redoc';
import React from 'react';

const ApiDocumentation: React.FC = () => {
  const redocOptions = {
    nativeScrollbars: true,
    theme: {
      colors: {
        primary: { main: '#2563eb' },
        success: { main: '#10b981' },
      },
      typography: {
        fontSize: '16px',
        fontFamily: 'Inter, sans-serif',
        headings: { fontFamily: 'Montserrat, sans-serif' },
      },
      sidebar: {
        backgroundColor: '#f8fafc',
        textColor: '#1e293b',
      },
    },
    hideDownloadButton: false,
    disableSearch: false,
    scrollYOffset: 60,
  };

  return (
    <RedocStandalone
      specUrl="/api/openapi.yaml"
      options={redocOptions}
      onLoaded={() => console.log('Documentation loaded')}
    />
  );
};

export default ApiDocumentation;

Implementation

Prepare your valid OpenAPI specification (YAML or JSON) and validate it with tools like Swagger Editor
Choose integration method: standalone HTML file, CDN, npm package, or CLI for static generation
Install Redoc via npm (`npm install redoc`) for React/Vue integration, or use standalone bundle via CDN
Configure theme options, navigation, and behavior according to your brand guidelines and UX needs
Customize SEO metadata (title, description, favicon) to optimize discoverability
Deploy documentation to your infrastructure (Netlify, Vercel, S3, GitHub Pages, or internal server)
Set up CI/CD pipeline to automatically regenerate documentation with each API update
Monitor usage via analytics and gather developer feedback for continuous improvement

Pro tip

For complex APIs with OAuth2 authentication or API keys, combine Redoc with an interactive testing environment like Swagger UI or Postman Collections. Redoc excels in visual presentation and navigation, while Swagger UI offers an execution playground. Host both versions in parallel: Redoc as the primary reference documentation, and Swagger UI for quick testing.

Redocly CLI: suite of tools to validate, bundle, and optimize your OpenAPI specifications before generation
Swagger Editor: online editor to create and validate OpenAPI files with real-time preview
Stoplight Studio: complete API design platform with automatic Redoc documentation generation
Spectral: OpenAPI linter to ensure quality and consistency of specifications before publication
Postman: API testing tool that can generate collections from OpenAPI specifications
GitHub Pages / Netlify: free static hosting solutions ideal for deploying your Redoc documentation

Redoc represents a professional API documentation solution that transforms technical specifications into superior developer experiences. Its adoption accelerates partner onboarding, reduces support tickets, and enhances your API offering in an ecosystem where documentation quality becomes a decisive competitive advantage.

Fundamentals

Benefits

Practical Example

Implementation

Pro tip

Themoneyisalreadyonthetable.

Themoneyisalreadyonthetable.

Fundamentals

Benefits

Practical Example

Implementation

Pro tip

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