Top AI Models for Voice & Realtime Agents

An expressive text-to-speech model for narration, character voices and dialogue in many languages.

Price basis

$0.08 / 1,000 characters

Interaction mode

Text-to-speech and multi-speaker dialogue

A low-latency speech model for assistants and interactive characters that need an expressive speaking voice.

Price basis

$0.04 / 1,000 characters

Interaction mode

Realtime text-to-speech / text-to-dialogue

Google's speech-generation model for expressive narration, character voices and dialogue in 130 languages.

Price basis

$0.50 text input · $9 audio output / 1M tokens

Interaction mode

Text-to-speech with two-speaker dialogue

Google's lower-cost speech-generation model for read-aloud features and high-volume audio in 101 languages.

Price basis

$0.50 text input · $6 audio output / 1M tokens

Interaction mode

Text-to-speech with two-speaker dialogue

OpenAI's full-duplex voice frontend for natural conversation that delegates deeper reasoning and actions to a separate backend agent.

Price basis

$0.05 / voice minute + backend usage

Interaction mode

Full-duplex voice frontend with delegated backend

Google's real-time voice model for responsive conversations with audio, text and visual context.

Price basis

Audio $0.005/min in · $0.018/min out

Interaction mode

Speech-to-speech with visual input and interleaved reasoning

A separate Gemini voice model that works through complex requests in the background while keeping the conversation going.

Price basis

Audio $0.005/min in · $0.018/min out

Interaction mode

Speech-to-speech with visual input and background reasoning

OpenAI's realtime speech-to-speech reasoning model for tool-using voice agents that also need text and image context.

Price basis

Audio $32 in · $64 out / 1M tokens

Interaction mode

Speech-to-speech with text/image context

Google's preview audio-to-audio model for low-latency dialogue with multimodal awareness, thinking, search grounding, and function calling.

Price basis

Audio $0.005/min in · $0.018/min out

Interaction mode

Realtime audio-to-audio, multimodal input

ElevenLabs' expressive realtime text-to-speech model for natural dialogue, emotional delivery, audio tags, and more than 70 languages.

Price basis

$0.04 / 1,000 characters

Interaction mode

Realtime text-to-speech / text-to-dialogue

Inworld's newest expressive realtime text-to-speech model, designed to remember conversational delivery and speak in more than 100 languages.

Price basis

$25 / 1M chars on demand; volume discounts

Interaction mode

Steerable realtime TTS with prior-audio context

SpaceXAI's current realtime speech-to-speech model for sub-second conversational agents with tool access.

Price basis

$0.08 / audio minute

Interaction mode

Realtime speech-to-speech with tools