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

# Overview

> Everything Fish Audio can do — and how to build with it

Fish Audio is a voice AI platform. Every core feature is available three ways: in the [web app](/overview/platform) (no code), through the [REST API](/api-reference/introduction), and via the official [SDK](/developer-guide/sdk-guide/quickstart).

## Core features

<CardGroup cols={2}>
  <Card title="Text to Speech" icon="microphone" href="/features/text-to-speech">
    Convert text into lifelike speech with the `s2.1-pro`, `s2-pro`, and `s1` models.
  </Card>

  <Card title="Speech to Text" icon="waveform" href="/features/speech-to-text">
    Transcribe audio to text with per-segment timestamps.
  </Card>

  <Card title="Voice Cloning" icon="clone" href="/features/voice-cloning">
    Clone a voice instantly from a clip, or train a persistent model.
  </Card>

  <Card title="Realtime Streaming" icon="bolt" href="/features/realtime-streaming">
    Stream audio as it generates — for voice agents and live apps.
  </Card>

  <Card title="Manage Voices" icon="sliders" href="/features/manage-voices">
    List, inspect, update, and delete your voice models.
  </Card>
</CardGroup>

## Also in the web app

These run in the browser, no code required — see the [Platform guide](/overview/platform).

<CardGroup cols={2}>
  <Card title="Voice Changer" icon="wand-magic-sparkles" href="/overview/platform">
    Transform existing audio into a different voice.
  </Card>

  <Card title="Story Studio" icon="book-open" href="/overview/platform">
    Produce multi-speaker, long-form audio — audiobooks and narration.
  </Card>

  <Card title="Music & Sound Effects" icon="music" href="/overview/platform">
    Generate music and cinematic sound effects from a prompt.
  </Card>

  <Card title="Audio Separation" icon="scissors" href="/overview/platform">
    Split audio into stems, and related processing utilities.
  </Card>
</CardGroup>

## Models

These text-to-speech models power most capabilities:

* **`s2.1-pro`** — the recommended production model, with improved quality, latency, and throughput over S2-Pro.
* **`s2.1-pro-free`** — the same model at \$0 for testing, prototyping, development, and smaller businesses, without TTFA or DPA guarantees.
* **`s2-pro`** — the previous-generation S2 model, with multi-speaker and natural-language expression control.
* **`s1`** — the previous generation, with `(parenthesis)` emotion tags.

See [Models Overview](/developer-guide/models-pricing/models-overview) and [Choosing a Model](/developer-guide/models-pricing/choosing-a-model) for the full lineup, languages, and limits.

## Pick your path

<CardGroup cols={2}>
  <Card title="Use the web app" icon="browser" href="/overview/platform">
    No code — generate audio, clone voices, and produce projects in your browser.
  </Card>

  <Card title="Build with the SDK" icon="code" href="/developer-guide/sdk-guide/quickstart">
    The Python library for your application.
  </Card>

  <Card title="Call the API" icon="terminal" href="/api-reference/introduction">
    Raw REST and WebSocket endpoints for any language.
  </Card>

  <Card title="Use your AI coding agent" icon="robot" href="/developer-guide/resources/coding-agents">
    Install the Fish Audio skill so your agent writes correct code.
  </Card>
</CardGroup>