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# Neuphonic

> Connect Neuphonic to Vapi to use its text-to-speech voices for your voice agent. Covers how to select a Neuphonic voice in the API.

Neuphonic is a text-to-speech provider you can use for your voice agent's voice. Connect Neuphonic to use its voices on a Vapi assistant. This page covers what Neuphonic is and how to select a voice.

## What is Neuphonic

Neuphonic is a text-to-speech provider that generates the spoken audio for a voice agent. On Vapi, you select a Neuphonic voice for an assistant.

You can use Neuphonic through Vapi's default integration, or use your own Neuphonic account by connecting it in [Integrations](/providers/integrations).

## Text-to-speech

Set `voice.provider` to `neuphonic` and `voice.voiceId` to a Neuphonic voice. Neuphonic offers many voices, you can browse and copy a voice's ID from the [Voice Library](/providers/voice/overview).

```bash
curl -X PATCH "https://api.vapi.ai/assistant/ASSISTANT_ID" \
  -H "Authorization: Bearer $VAPI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "voice": { "provider": "neuphonic", "voiceId": "VOICE_ID" }
  }'
```

For additional API configuration options, review the [`NeuphonicVoice` fields](/api-reference/assistants/create#request.body.voice.NeuphonicVoice) in the Create Assistant API reference.

## Supported languages

Set `voice.language` to a supported language. Neuphonic requires a language, and the available voices depend on it.

| Language          | Language code |
| ----------------- | ------------- |
| Dutch             | `nl`          |
| English           | `en`          |
| English and Hindi | `en-hi`       |
| German            | `de`          |
| Hindi             | `hi`          |
| Spanish           | `es`          |

## Related

#### [Voices](/providers/voice/overview)

Compare every text-to-speech provider Vapi supports.