openapitools/openapi-generator

📈 Trending★ 26,255JavaAudience · developerComplexity · 2/5ActiveLicenseSetup · moderate

Mindmap

mindmap
  root((repo))
    What it does
      Generates client code
      Generates server stubs
      Generates documentation
    Input & Output
      Takes OpenAPI specs
      Outputs 50+ languages
      Produces typed libraries
    Use cases
      Integrate third-party APIs
      Build your own API
      Generate SDKs
    Tech stack
      Java
      OpenAPI spec format
      Multiple language targets
    Audience
      Vibe coders
      Backend developers
      API maintainers

mindmap root((repo)) What it does Generates client code Generates server stubs Generates documentation Input & Output Takes OpenAPI specs Outputs 50+ languages Produces typed libraries Use cases Integrate third-party APIs Build your own API Generate SDKs Tech stack Java OpenAPI spec format Multiple language targets Audience Vibe coders Backend developers API maintainers

Things people build with this

USE CASE 1

Generate a fully-typed Python client library from a REST API's OpenAPI spec in minutes instead of writing it by hand.

USE CASE 2

Create server skeleton code in Go or Java to jumpstart building your own API with correct request/response handling.

USE CASE 3

Automatically generate up-to-date API documentation and client SDKs whenever your API specification changes.

Tech stack

JavaOpenAPIPythonJavaScriptGoSwiftPHP

Getting it running

Difficulty · moderate Time to first run · 30min

Requires Java runtime and understanding of OpenAPI spec format to generate first output.

Use freely for any purpose, including commercial use, as long as you keep the copyright notice and license text.

In plain English

OpenAPI Generator is a tool that automatically generates code from an API specification (a structured document describing how an API works, what endpoints it has, what data it accepts, and what it returns). Instead of manually writing the code to connect to a third-party API, you give this tool the API's specification file and it produces ready-to-use code for you. An API (Application Programming Interface) is how software talks to other software, for example, when your app fetches weather data from a weather service, or processes a payment through Stripe. Every time your app calls an external service, it's using that service's API. OpenAPI Generator can produce several types of output: client libraries (code that lets your app talk to the API), server stubs (skeleton code for building your own API), and documentation. It supports over 50 programming languages and frameworks as output targets, Python, JavaScript, Java, Go, Swift, PHP, and many others. For a vibe coder using Lovable, Cursor, or Bolt who needs to integrate with a third-party API, this tool can eliminate hours of tedious boilerplate code. If the service you want to integrate has published an OpenAPI specification (most modern APIs do), you can generate a complete, correctly-typed client library in your language of choice in minutes. The tool is used by major companies including Datadog, Adyen, and OneSignal for generating their own official SDK libraries. It's free, open source, and available as a command-line tool or via build system plugins.

Copy-paste prompts

Prompt 1

I have an OpenAPI spec file for a third-party API. How do I use OpenAPI Generator to create a Python client library I can import into my project?

Prompt 2

Show me how to generate a JavaScript/TypeScript client from an OpenAPI spec using the command line, and what files it will create.

Prompt 3

I want to generate server boilerplate code in Java from an OpenAPI spec. What command do I run and what will the output structure look like?

Prompt 4

How do I integrate OpenAPI Generator into my build pipeline so client code regenerates automatically when the API spec changes?

Open on GitHub → Explain another repo

Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.