# Models & Languages Overview

## Models

| Model                                                                | Description & Use                                                                                                                                                                                                                               |
| -------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| [Flux TTS](/guides/home-docs-tts-models-languages-overview#flux-tts) | Our latest-generation, conversation-native voice model — streaming-first, turn-based, and expressive by default. **Recommended for all new builds**: voice agents, customer service, IVR, and general-purpose synthesis. Served on `/v2/speak`. |
| [Aura-2](/guides/home-docs-tts-models-languages-overview#aura-2)     | Our widest-language model, with voices across seven languages. Recommended when you need synthesis in a language Flux TTS doesn’t cover yet. Served on `/v1/speak`.                                                                             |
| [Aura](/guides/home-docs-tts-models-languages-overview#aura)         | Our first-generation text-to-speech model. English voices only. Served on `/v1/speak`.                                                                                                                                                          |

**Start with Flux TTS.** It’s our best-sounding, most accurate model and the default recommendation for every use case it serves. Flux TTS is English-only today — for Spanish, German, French, Dutch, Italian, or Japanese, use Aura-2 until Flux TTS’s multilingual voices ship.

:::callout{intent="info"}
All models default to `language=en` (via the voice’s model string). A `model` is required on every request — Flux TTS on `/v2/speak`, Aura-2 and Aura on `/v1/speak`.
:::

### Example

To request a voice, set the `model` to the voice you want. Aura-2 and Aura use `/v1/speak`:

```bash title="cURL (Aura-2, /v1/speak)"
curl "https://api.deepgram.com/v1/speak?model=aura-2-thalia-en" \
  -H "Authorization: Token YOUR_DEEPGRAM_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{ "text": "Hello, how are you?" }' \
  --output audio.mp3
```

Flux TTS uses `/v2/speak` (streaming WebSocket and batch REST). See [Getting Started with Flux TTS](/guides/flux-tts-quickstart).

:::callout{intent="warning"}
Replace `YOUR_DEEPGRAM_API_KEY` with your [Deepgram API Key](/guides/guides-docs-create-additional-api-keys).
:::

## Flux TTS

Flux TTS is Deepgram’s best text-to-speech model and the recommended choice for every English use case — real-time voice agents, customer service, IVR, and pre-rendered audio alike. It’s conversation-native: streaming-first, turn-based, expressive by default, and consistent across turns, with native interruption handling and strong accuracy on the strings that trip up agents in production (alphanumerics, drug names, and other hard-to-say entities). Model strings follow the format `flux-{voice}-{language}` (e.g. `flux-alexis-en`), and `model` is required on every `/v2/speak` connection.

| Model Option      | Language                                                                            |
| ----------------- | ----------------------------------------------------------------------------------- |
| `flux-{voice}-en` | English (American, British, Irish, Australian, Indian, Singaporean, Filipino): `en` |

See the full [Flux TTS Voices & Languages](/guides/flux-tts-voices) catalog for every voice and its characteristics.

## Aura-2

Aura-2 is Deepgram’s widest-language text-to-speech model, with voices across seven languages. Reach for it when you need synthesis in a language Flux TTS doesn’t cover yet; for English, build on [Flux TTS](/guides/home-docs-tts-models-languages-overview#flux-tts). Model strings follow the format `aura-2-{voice}-{language}` (e.g. `aura-2-thalia-en`).

| Model Option        | Language                                                                  |
| ------------------- | ------------------------------------------------------------------------- |
| `aura-2-{voice}-en` | English (American, British, Australian, Filipino): `en`                   |
| `aura-2-{voice}-es` | Spanish (Mexican, Peninsular, Colombian, Argentine, Latin American): `es` |
| `aura-2-{voice}-de` | German: `de`                                                              |
| `aura-2-{voice}-fr` | French: `fr`                                                              |
| `aura-2-{voice}-nl` | Dutch: `nl`                                                               |
| `aura-2-{voice}-it` | Italian: `it`                                                             |
| `aura-2-{voice}-ja` | Japanese: `ja`                                                            |

See the full [Aura Voices & Languages](/guides/aura-tts-models) catalog for every voice, accent, and audio sample. Select Spanish voices (Aquila, Carina, Diana, Javier, Selena) support English–Spanish codeswitching.

## Aura

Aura is Deepgram’s first-generation text-to-speech model. English voices only, served on `/v1/speak`.

| Model Option      | Language                                 |
| ----------------- | ---------------------------------------- |
| `aura-{voice}-en` | English (American, British, Irish): `en` |

See the [Aura Voices & Languages](/guides/aura-tts-models#aura-1-all-available-english-voices) catalog for the full list.

***

## Related pages

- [Amazon SageMaker](./amazon-sagemaker-index.md)
- [Aura](./aura-index.md)
- [Changelog](../changelog.md)
- [Custom Vocabulary](./custom-vocabulary-index.md)
- [Deepgram's Docs](../index.md)
- [Deployment](./deployment-index.md)
- [Docker/Podman](./docker-podman-index.md)
- [Features](./features-index.md)
- [Flux TTS](./flux-tts-index.md)
- [Formatting](./formatting-index.md)

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