ResourcesIntegrationsVoices (Text-to-speech)

Smallest AI

Use Smallest AI’s text-to-speech voices for your Vapi voice agent.

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

What is Smallest AI

Smallest AI is a text-to-speech provider focused on low-latency speech synthesis. On Vapi, you select a Smallest AI voice for an assistant.

You can use Smallest AI through Vapi’s default integration, or use your own Smallest AI account by connecting it in Integrations.

Text-to-speech

Set voice.provider to smallest-ai, voice.model to lightning, and voice.voiceId to a voice. Smallest AI offers many voices, you can browse and copy a voice’s ID from the Voice Library.

$curl -X PATCH "https://api.vapi.ai/assistant/ASSISTANT_ID" \
>  -H "Authorization: Bearer $VAPI_API_KEY" \
>  -H "Content-Type: application/json" \
>  -d '{
>    "voice": { "provider": "smallest-ai", "model": "lightning", "voiceId": "emily" }
>  }'

For additional API configuration options, review the SmallestAIVoice fields in the Create Assistant API reference.

Voices

Compare every text-to-speech provider Vapi supports.