> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/fastapi/fastapi/llms.txt
> Use this file to discover all available pages before exploring further.

# Introduction to FastAPI

> Learn about FastAPI, a modern, high-performance Python web framework for building APIs with automatic documentation and type safety

# Welcome to FastAPI

FastAPI is a modern, fast (high-performance) web framework for building APIs with Python based on standard Python type hints.

## What is FastAPI?

FastAPI is designed to help you build robust APIs quickly and efficiently. It combines the best aspects of Python's type system with automatic API documentation, making it one of the most developer-friendly frameworks available.

<CardGroup cols={2}>
  <Card title="Get started" icon="rocket" href="/installation">
    Install FastAPI and set up your development environment
  </Card>

  <Card title="Quick start" icon="bolt" href="/quickstart">
    Build your first API in minutes
  </Card>

  <Card title="First steps" icon="graduation-cap" href="/tutorial/first-steps">
    Learn the fundamentals with our tutorial
  </Card>

  <Card title="API reference" icon="book" href="/api-reference">
    Explore the complete API documentation
  </Card>
</CardGroup>

## Key features

### Type-driven development

FastAPI leverages Python's type hints to provide automatic validation, serialization, and editor support. Write type-safe code with full autocompletion.

### Automatic interactive documentation

Every FastAPI application comes with automatically generated, interactive API documentation at `/docs` (Swagger UI) and `/redoc` (ReDoc). No configuration required.

### High performance

FastAPI is built on Starlette and Pydantic, making it one of the fastest Python frameworks available. Performance is on par with NodeJS and Go.

### Dependency injection

Powerful and intuitive dependency injection system that makes it easy to manage dependencies, share code, and implement security patterns.

### Security and authentication

Built-in support for OAuth2, JWT tokens, HTTP Basic authentication, API keys, and more. Security utilities make it simple to protect your endpoints.

### Standards-based

Based on open standards for APIs: OpenAPI (formerly Swagger) and JSON Schema. This means automatic client code generation and integration with existing tools.

## Why choose FastAPI?

<Note>
  FastAPI combines speed of development with runtime performance, helping you build production-ready APIs faster while maintaining high standards.
</Note>

Key benefits include:

* **Fast to code**: Increase development speed by 200-300%
* **Fewer bugs**: Reduce developer-induced errors by approximately 40%
* **Intuitive**: Great editor support with completion everywhere
* **Easy**: Designed to be easy to use and learn
* **Robust**: Get production-ready code with automatic documentation

## Requirements

FastAPI stands on the shoulders of giants:

* **Starlette** for the web parts
* **Pydantic** for the data validation and settings management

<Info>
  FastAPI requires Python 3.10 or higher.
</Info>

## Next steps

Ready to get started? Follow our installation guide and build your first API:

<Steps>
  <Step title="Install FastAPI">
    Follow the [installation guide](/installation) to set up FastAPI
  </Step>

  <Step title="Build your first API">
    Complete the [quick start guide](/quickstart) to create a working API
  </Step>

  <Step title="Learn the fundamentals">
    Work through the [first steps tutorial](/tutorial/first-steps)
  </Step>
</Steps>