# API First

FusionAuth loves APIs. By leveraging our API-first approach, you can streamline user management, enhance security, and integrate seamlessly with your existing systems.

## Manage Your Instance

FusionAuth lets you manage tenants, applications, users, and more using our robust APIs. The FusionAuth admin UI is built on top of these RESTful APIs, so you can use the same APIs the FusionAuth team does.

## SDKs

Prefer python to JSON? Or fetch to GET? Use our SDKs and client libraries, which are thin layers over our APIs, to control your instance. Support for Python, PHP, .NET, Java, Golang, JavaScript, and Ruby available, as well as a Terraform provider.

## API Granular Control

Maintain precise control over your API keys by limiting them to specific REST methods and endpoints. This granular access control ensures that each key has only the permissions it needs, enhancing security.

## Limit Access To IP Ranges

With IP ACLs, you can limit an API key for usage by an IP address range. Perfect for CI/CD or backend processes that need elevated privileges.

## Tenant Locked Keys

Implement a defense-in-depth strategy by locking API keys to specific tenants. This approach limits the blast radius of any compromised key.

## An API For API Keys

Generate and manage API keys programmatically, allowing you to create unique, secure keys for any software that needs to interact with FusionAuth. This automation enhances security and simplifies key management.

### 20M+

Downloads

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Logins/sec Supported

### 99.99%

Uptime SLA

### 24/7

Engineer-led Support

## Complete Auth for Any App

FusionAuth is a complete solution with no sacrifices. We got this. Go build something awesome.

**Quickstarts**  
Step-by-step guides to quickly integrate FusionAuth into your application.

**Modern Guide to OAuth**  
Discover what OAuth 2.0 is, how it works, and its importance in securing and managing access to online resources.