OpenAPI  Specification


The World Standard for RESTful APIs


The OpenAPI Specification was donated to the Linux Foundation under the OpenAPI Initiative in 2015. The specification creates a RESTful interface for easily developing and consuming an API by effectively mapping all the resources and operations associated with it.

OAS 2.0OAS 3.0

OpenAPI Specification & Swagger Tools 

The Swagger tools were developed by the team behind the original "Swagger" Specification. Swagger offers the most powerful and easiest to use tools to take full advantage of the OpenAPI Specification.

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Why OpenAPI Specification?


Streamline Your Workflow

Streamline your API’s build process by keeping its design, documentation, and implementation synchronized and updated automatically

Restraint-Free Build

Develop APIs in the technology stack of your choice with client libraries and server templates in every popular language

Open & Globally Supported

The OpenAPI Specification is a community-driven open specification within the Open API Initiative, a Linux Foundation Collaborative Project.


Unlocking the Power of Your APIs with OAS 

The OpenAPI Specification can be implemented across the API lifecycle.


OAS offers the complete format for designing APIs, defining resources and operations before writing code a line of code.


Visualize your APIs operations and let internal developers and external consumers quickly adopt your API.

Client & Server Generation

Generate scaffolding for server stubs and client SDKs, based on your OAS definition


Automate test case generation by defining a successful response in your OAS definition.


Use the operations defined in your OAS generation to create API monitors.


Supported by leading API gateways like AWS, IBM, Apigee, and more.

Get Started with OAS with Swagger

The Swagger tools support advanced Swagger users, and teams that are just beginning their journey with the OpenAPI Specification.

Learn OpenAPI

New to OpenAPI? We have resources and documentation to help you get started.

OAS Docs

Generate Your OAS Definition

Need to document an existing set of APIs with OAS? Swagger has you covered.

Generate OAS