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Mistral Launches Voxtral 3 With Four Speech Models and a LiveKit-Based Voice Agent SDK, Pricing Voice Agents From $0.04 per Minute

Mistral AI's Voxtral 3 post lists three transcription models, a text-to-speech model at $13 per 1M characters and a voice agent SDK built on LiveKit; benchmark claims are Mistral's own.

AI & Machine Learning Models
Mistral AI Voxtral speech-to-text text-to-speech voice agents LiveKit API pricing
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Overview

Mistral AI has introduced Voxtral 3, which it describes in a post on its website as “a new family of state-of-the-art speech-to-text and text-to-speech models, alongside a voice agent SDK that brings listening, thinking, tool calling, and speaking into a single real-time streaming pipeline.” The post, published October 22 according to the page’s publication metadata, says the models are available through the Mistral API.

What We Know

According to Mistral, the release has four priced API models:

  • Voxtral Small Transcribe 3, described as the highest-accuracy transcription model, at $0.0040 per minute. Mistral says it supports over 50 languages, diarization (identifying who spoke) and context biasing, where key terms are supplied to improve recall on technical vocabulary.
  • Voxtral Mini Transcribe 3, a 4B-parameter model priced at $0.0035 per minute for batch audio.
  • Voxtral Mini Transcribe Realtime 3, priced at $0.008 per minute, which Mistral says delivers sub-500ms latency. The post’s body text gives its language coverage as “over 35 languages,” while the product card on the same page says “40+ languages.”
  • Voxtral Mini TTS 3, a text-to-speech model priced at $13 per 1M characters, which Mistral says supports 35+ languages and 50+ dialects and adjusts emotion, pace and emphasis to context.

The voice agent SDK is, per Mistral, built on LiveKit. The post describes a pipeline in which Voxtral Mini Transcribe Realtime 3 listens and detects when the caller has finished speaking, “a general model—like Mistral Small—reasons and calls tools,” and Voxtral TTS replies. Mistral says each turn completes in under one second and that the agent stops talking when the caller cuts in. It says agents can answer and place calls over SIP and run in browsers and apps over WebRTC.

Mistral lists voice agent API pricing of $0.04 per minute with Mistral Small 4 for reasoning and $0.08 per minute with a larger model. It also describes a “Pro Voice” adaptation feature that it says can reproduce a speaker’s character, emotional range and speaking style using 30 minutes of audio.

On deployment, Mistral says Voxtral 3 is available through its API “hosted through our European, US, and global endpoints,” or for self-deployment on an organization’s own infrastructure. For running the full stack on-premises or in a private cloud, the post directs readers to talk to Mistral’s team.

Benchmarks and Caveats

The performance claims come from Mistral’s own post. For transcription, Mistral says the Small model “outperforms Whisper, Scribe v2 and Gemini 3.5 Transcribe.” On the text-to-speech side, Mistral says that at $13 per 1M characters “Voxtral TTS costs less to run than comparable models from OpenAI TTS-1, Deepgram, ElevenLabs Flash and Gemini Flash.” Several of the post’s text-to-speech charts are labeled “Internal eval,” and their captions say the judge model was gemini-3.8-flash, with prices taken from vendor pricing pages. The Voice Code Bench chart is attributed to BeSimple AI. No independent evaluation of Voxtral 3 appears in the sources reviewed for this article.

What We Don’t Know

The announcement text does not describe a weights release or a license for Voxtral 3; it points on-premises customers to Mistral’s team. That contrasts with Mistral’s earlier Voxtral TTS model, which TechCrunch described in March as “a new open source text-to-speech model” supporting nine languages, a release The Machine Herald previously reported. Whether the Voxtral 3 models will be published for download is not stated in the post.

The post also does not reconcile its two figures for realtime transcription language coverage, so developers planning around a specific language should check the current model documentation.

Context

In March, Pierre Stock, VP of science operations at Mistral AI, told TechCrunch: “We plan to have an end-to-end platform that can handle multimodal streams of input, including audio, text, and image and output as well.” The Voxtral 3 post packages transcription, reasoning, tool calling and speech synthesis behind one SDK; it does not reference Stock’s remark.