# OpenAPI Generator

OpenAPI Generator allows generation of API client libraries (SDK generation), server stubs, documentation and configuration automatically given an OpenAPI Spec (v2, v3)

Repository: https://github.com/OpenAPITools/openapi-generator
Canonical: https://ross.abutalabs.com/products/openapi-generator
Homepage: https://openapi-generator.tech
Language: Java
License: Apache-2.0
License Family: permissive
Topics: rest-api, rest-client, sdk, generator, restful-api, api, api-client, api-server, openapi3, openapi, rest, openapi-generator, hacktoberfest
Last push: 2026-08-26T17:08:18+00:00
Link (homepage): https://openapi-generator.tech
Link (site_page): https://openapi-generator.tech/docs/installation
Link (site_page): https://openapi-generator.tech/docs/generators
Link (site_page): https://openapi-generator.tech/docs/roadmap
Link (site_page): https://openapi-generator.tech/docs/faq

## Health v2 (maintenance only)
Score: 95/100 (v2, computed 2026-09-02T17:46:02.011165+00:00)
- activity 99, release rhythm 87, longevity 100
- inputs: {"age_days": 3035, "days_push": 7, "days_rel": 9, "gap_med": 39.5, "n_releases_24m": 17}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 26685, forks 7660 (observed 2026-08-28T04:11:47.086604+00:00)

## What it is
OpenAPI Generator is a Java-based tool that generates API client libraries, server stubs, documentation, and configuration from OpenAPI 2.0/3.x specifications. It supports 50+ client generators and 40+ server generators across many languages, with customizable Mustache templates and Maven/Gradle/CI integrations.

## Use cases
- generate an API client SDK from an OpenAPI spec
- generate server stubs from an OpenAPI document
- generate static HTML documentation for a REST API
- convert OpenAPI 2.0 specs to OpenAPI 3.x
- generate a TypeScript or Python client for a REST API
- auto-generate and distribute official SDKs for an API
- generate MySQL or GraphQL schemas from an OpenAPI document

## When to choose
- you maintain an OpenAPI-documented REST API and want clients or stubs in multiple languages
- you want customizable code generation via Mustache templates
- you need build-tool integration via Maven, Gradle, sbt, or CI/CD pipelines

## When to avoid
- your API is not described by an OpenAPI/Swagger specification
- you need GraphQL or gRPC-first code generation rather than REST
- you want a lightweight runtime library rather than a build-time generator

## Facets
- artifact type: cli-tool
- maturity: stable
- function: sdk, api-framework, documentation, cli, developer-tools
- domain: apis, web-development, developer-tools, backend, documentation
- platform: windows, cli, jvm
- tags: openapi, swagger, rest-api, code-generation, client-generation, server-stubs, mustache-templates, maven-plugin, gradle-plugin, linux, macos, docker, nodejs

## Member repositories
- OpenAPITools/openapi-generator (main) score 95
- OpenAPITools/openapi-generator-cli (sdk) score 95

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:11:47.086604+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:55:50.223679+00:00, confidence not recorded.
  - readme: https://github.com/OpenAPITools/openapi-generator (fetched 2026-08-28T04:11:47.086604+00:00, sha 5a4fd10ef6ed)
  - homepage: https://openapi-generator.tech (fetched 2026-08-29T07:52:26.440671+00:00, sha 4636230c92df)
  - site_page: https://openapi-generator.tech/docs/installation (fetched 2026-08-29T07:52:26.450946+00:00, sha 992969e0d9e0)
  - site_page: https://openapi-generator.tech/docs/generators (fetched 2026-08-29T07:52:26.454090+00:00, sha dbbaf56c348f)
  - site_page: https://openapi-generator.tech/docs/roadmap (fetched 2026-08-29T07:52:26.457216+00:00, sha f9aa6aaddeca)
  - site_page: https://openapi-generator.tech/docs/faq (fetched 2026-08-29T07:52:26.460028+00:00, sha 29eed3af2049)
  - site_page: https://openapi-generator.tech/docs/customization (fetched 2026-08-29T07:52:26.462645+00:00, sha a75b1ba561f4)
  - site_page: https://openapi-generator.tech/docs/integrations (fetched 2026-08-29T07:52:26.466249+00:00, sha 78c4bb1a0781)
- Data as of 2026-08-30T08:39:29.467469+00:00.