Skip to content
SPECIFICTION
Get listed

OpenAPI Generator

openapi-generator.tech

Free plan WebWindowsmacOSLinuxSelf-hosted
Visit openapi-generator.tech
Spec score 7.7 #11 of 25 in API Generation Software

What it is

OpenAPI Generator produces API clients, server stubs, and documentation from OpenAPI 2.0 and 3.x documents. It offers more than 50 client generators and server stub generation for over 40 languages and technologies, including Java, Kotlin, Go, and PHP. Other outputs include Apache2 configuration, MySQL, GraphQL schemas, and formats such as HTML and Cwiki. It can also convert OpenAPI 2.0 documents into OpenAPI 3.x JSON or YAML. Generated output can be adapted with Mustache templates, configuration-provided files and extensions, or custom generators. Installation choices include npm, Homebrew, Scoop, PyPI, Docker, JAR, JBang, and a Bash launcher. The project documents Gradle, Maven, sbt, Bazel, GitHub, and CI/CD integrations. Supported operating systems include Linux, macOS, and Windows, though installer availability varies by system. The JAR option requires Java 11 or later. The project is free and describes a Slack community for questions and guidance.

Spec sheet

Purpose
Generates clients, servers, and documentation from OpenAPI 2.0 and 3.x documents.Read 29 Sep 2026 · openapi-generator.tech
Integrations
The project documents Gradle, Maven, sbt, Bazel, GitHub, and CI/CD integrations; Cake is a third-party add-in.Read 29 Sep 2026 · openapi-generator.tech
Client generators
The homepage states it has 50+ client generators.Read 29 Sep 2026 · openapi-generator.tech
Community support
The project describes an active Slack community of users, contributors, and core team members for guidance and questions.Read 29 Sep 2026 · openapi-generator.tech
Customization
Users can replace templates with Mustache templates, provide additional files and extensions through configuration, or create custom generators.Read 29 Sep 2026 · openapi-generator.tech
Installation
The CLI can be installed through npm, Homebrew, Scoop, PyPI, Docker, JAR, JBang, or a Bash launcher script.Read 29 Sep 2026 · openapi-generator.tech
OpenAPI conversion
It supports generating newer JSON or YAML OpenAPI 3.x documents from OpenAPI 2.0.Read 29 Sep 2026 · openapi-generator.tech
Other outputs
It includes generators for Apache2 configuration, MySQL, GraphQL schemas, and documentation formats such as HTML and Cwiki.Read 29 Sep 2026 · openapi-generator.tech
Runtime requirement
The JAR installation requires at least Java 11.Read 29 Sep 2026 · openapi-generator.tech
Server generators
It can generate server stubs for 40+ languages and technologies, including Java, Kotlin, Go, and PHP.Read 29 Sep 2026 · openapi-generator.tech
Sponsorship
The project invites individual and company sponsorship through Open Collective.Read 29 Sep 2026 · openapi-generator.tech
Supported operating systems
The installation page lists Linux, macOS, and Windows support for npm, PyPI, Docker, JAR, and JBang; Homebrew is listed for macOS and Scoop for Windows.Read 29 Sep 2026 · openapi-generator.tech

Plans and prices

OpenAPI Generator Free Open source generator for API clients, server stubs, documentation, and configurations Read 29 Sep 2026 · openapi-generator.tech

Every OpenAPI Generator plan and price →

Strong points and limits

Strong points

  • More than 50 client generators
  • Generates server stubs for 40+ languages and technologies
  • Supports Mustache templates and custom generators
  • Free and available through multiple installation routes

Limits

  • JAR installation requires Java 11 or later
  • Installer options vary by operating system

Who it suits

It suits developers who need to generate API clients, server stubs, or documentation from OpenAPI specifications. Template and custom-generator options are relevant for teams that need to shape generated output.

Verdict

OpenAPI Generator covers a broad range of client and server outputs and allows substantial customization. Its free availability and multiple installation paths make it worth considering when generated code is part of an API workflow.

Where Specifiction places it

Alternatives to OpenAPI GeneratorAll alternatives →