Amazon API Gateway
Developer Guide

What Is Amazon API Gateway?

Amazon API Gateway is an AWS service for creating, publishing, maintaining, monitoring, and securing REST and WebSocket APIs at any scale. API developers can create APIs that access AWS or other web services as well as data stored in the AWS Cloud. As an API Gateway API developer, you can create APIs for use in your own client applications (apps). Or you can make your APIs available to third-party app developers. For more information, see Who Uses API Gateway?.

API Gateway creates REST APIs that:

  • Are HTTP-based.

  • Adhere to the REST protocol, which enables stateless client-server communication.

  • Implement standard HTTP methods such as GET, POST, PUT, PATCH and DELETE.

For more information about API Gateway REST APIs, see Use API Gateway to Create REST APIs and Creating a REST API in Amazon API Gateway.

API Gateway creates WebSocket APIs that:

  • Adhere to the WebSocket protocol, which enables stateful, full-duplex communication between client and server.

  • Route incoming messages and based on message content.

For more information about API Gateway WebSocket APIs, see Use API Gateway to Create WebSocket APIs and About WebSocket APIs in API Gateway.


Despite the name, API Gateway is not required for developing apps or services using existing Amazon or AWS APIs. If you're looking for information about those, try these sources.

Architecture of API Gateway

The following diagram shows API Gateway architecture.

                API Gateway Architecture Diagram

As shown in the diagram, an app (or client application) gains programmatic access to AWS services, or a website on the internet, through one or more APIs, which are hosted in API Gateway. The app is at the API's frontend. The integrated AWS services and websites are located at the API's backend.

With Amazon API Gateway, you can build an API to provide your users with an integrated and consistent developer experience to build AWS cloud-based applications.

Features of API Gateway

Amazon API Gateway offers features such as the following:

For a complete list of API Gateway feature releases, see Document History.

Accessing API Gateway

You can access Amazon API Gateway in the following ways:

Part of AWS Serverless Infrastructure

Together with AWS Lambda, API Gateway forms the app-facing part of the AWS serverless infrastructure. For an app to call publicly available AWS services, you can use Lambda to interact with required services and expose Lambda functions through API methods in API Gateway. AWS Lambda runs your code on a highly available computing infrastructure. It performs the necessary execution and administration of computing resources. To enable serverless applications, API Gateway supports streamlined proxy integrations with AWS Lambda and HTTP endpoints.

How to Get Started with Amazon API Gateway

For a quick introduction to Amazon API Gateway, see the following topics: