Voxtral-Mini-4B-Realtime-2602

Voxtral Mini 4B Realtime 2602 is a **multilingual, realtime speech-transcription model** and among the first open-source solutions to achieve accuracy comparable to offline systems with a delay of **<500ms**. It supports **13 languages** and outperforms existing open-source baselines across a range of tasks, making it ideal for applications like voice assistants and live subtitling. Built with a **natively streaming architecture** and a custom causal audio encoder - it allows configurable transcription delays (240ms to 2.4s), enabling users to balance **latency and accuracy** based on their needs. At a **480ms delay**, it matches the performance of leading offline open-source transcription models, as well as realtime APIs. As a **4B-parameter model**, is optimized for **on-device deployment**, requiring minimal hardware resources. It runs in realtime with on devices minimal hardware with throughput exceeding 12.5 tokens/second. This model is released in **BF16** under the **Apache-2 license**, ensuring flexibility for both research and commercial use. For more details, see our: - [Blog post](https://mistral.ai/news/voxtral-transcribe-2) - [Demo](https://huggingface.co/spaces/mistralai/Voxtral-Mini-Realtime) - [Technical report](https://arxiv.org/abs/2602.11298) - [vLLM's blog on streaming input](https://blog.vllm.ai/2026/01/31/streaming-realtime.html) Voxtral Mini 4B Realtime consists of two main architectural components: - **≈3.4B Language Model** - **≈970M Audio Encoder** - The audio encoder was trained from scratch with causal attention enabling streaming capability - Both the audio encoder as well as the LLM backbone use sliding window attention allowing for "infinite" streaming - For more details, refer to the [technical report](https://arxiv.org/abs/2602.11298) The Voxtral Mini 4B Realtime model offers the following capabilities: - **High-Quality Transcription**: Transcribe audio to text with confidence. - **Multilingual**: Supports dozens of languages, making it perfect for multilingual transcription tasks. - **Real-Time**: Fast streaming ASR model, enabling real-time transcription use cases. - **Configurable Transcription Delays**: Customize the transcription delay to balance quality and latency, from 80ms to 2.4s. **Real-Time Transcription Purposes:** - Private meeting transcriptions - Live subtitle creation - Real-time assistants with speech understanding - And more Bringing real-time transcription capabilities to all. We recommend deploying with the following best practices: - Always set the temperature to 0.0 - A single text-token is worth 80ms. Hence, make sure to set your `--max-model-len` accordingly. To live-record a 1h meeting, you need to set `--max-model-len >= 3600 / 0.8 = 45000`. In theory, you should be able to record with no limit; in practice, pre-allocations of RoPE parameters among other things limits `--max-model-len`. For the best user experience, we recommend to simply instantiate vLLM with the default parameters which will automatically set a maximum model length of 131072 (~ca. 3h). - We strongly recommend using websockets to set up audio streaming sessions. For more info on how to do so, check [Usage](#usage). - We recommend using a delay of 480ms as we found it to be the sweet spot of performance and low latency. If, however, you want to adapt the delay, you can change the `"transcription_delay_ms": 480` parameter in the [tekken.json](https://huggingface.co/mistralai/Voxtral-Mini-4B-Realtime-2602/blob/main/tekken.json) file to any multiple of 80ms between 80 and 1200, as well as 2400 as a standalone value. We compare Voxtral Mini 4B Realtime to similar models - both offline models and realtime. Voxtral Mini 4B Realtime is competitive to leading offline models and shows significant gains over existing open-source realtime solutions. The model can also be deployed with the following libraries: - [`vllm (recommended)`](https://github.com/vllm-project/vllm): See [here](#vllm-recommended) - [`transformers`](https://github.com/huggingface/transformers): See [here](#transformers) - [`executorch` (untested)](https://github.com/pytorch/executorch/tree/main/examples/models/voxtral_realtime): See [here](#executorch-untested) - *Community Contributions*: See [here](#community-contributions-untested) > [!Tip] > We've worked hand-in-hand with the vLLM team to have production-grade support for Voxtral Mini 4B Realtime 2602 with vLLM. > Special thanks goes out to [Joshua Deng](https://github.com/joshuadeng), [Yu Luo](https://github.com/ErickLuo90), [Chen Zhang](https://github.com/heheda12345), [Nick Hill](https://github.com/njhill), [Nicolò Lucchesi](https://github.com/NickLucche), [Roger Wang](https://github.com/ywang96), and [Cyrus Leung](https://github.com/DarkLight1337) > for the amazing work and help on building a production-ready audio streaming and realtime system in vLLM. > [!Warning] > Due to its novel architecture, Voxtral Realtime is currently only support in vLLM. We very much welcome community contributions > to add the architecture to [Transformers](https://github.com/huggingface/transformers) and [Llama.cpp](https://github.com/ggml-org/llama.cpp). We've worked hand-in-hand with the vLLM team to have production-grade support for Voxtral Mini 4B Realtime 2602 with vLLM. [vLLM](https://github.com/vllm-project/vllm)'s [new Realtime API](https://docs.vllm.ai/en/latest/serving/openai_compatible_server/?h=realtime#realtime-api) is perfectly suited to run audio streaming sessions with the model. Make sure to install [vllm](https://github.com/vllm-project/vllm) from the nightly pypi package. See [here](https://docs.vllm.ai/en/latest/getting_started/installation/) for a full installation guide. uv pip install -U vllm Doing so should automatically install [`mistral_common >= 1.9.0`](https://github.com/mistralai/mistral-common/releases/tag/v1.9.0). To check: python -c "import mistral_common; print(mistral_common.__version__)" You can also make use of a ready-to-go [docker image](https://github.com/vllm-project/vllm/blob/main/docker/Dockerfile) or on the [docker hub](https://hub.docker.com/layers/vllm/vllm-openai/nightly/images/sha256-6ae33f5001ab9d32346ce2c82c660fe57021c4f0c162ed0c60b843319829b810). Make sure to also install all required audio processing libraries: uv pip install soxr librosa soundfile Also we recommend using Transformers v5 as v4 can clutter the terminal with unnecessary warnings (see [here](https://github.com/vllm-project/vllm/issues/34642)) uv pip install --upgrade transformers Due to size and the BF16 format of the weights - `Voxtral-Mini-4B-Realtime-2602` can run on a single GPU with >= 16GB memory. The model can be launched in both "eager" mode: VLLM_DISABLE_COMPILE_CACHE=1 vllm serve mistralai/Voxtral-Mini-4B-Realtime-2602 --compilation_config '{"cudagraph_mode": "PIECEWISE"}' Additional flags: * You can set `--max-num-batched-tokens` to balance throughput and latency, higher means higher throughput but higher latency. * You can reduce the default `--max-model-len` to allocate less memory for the pre-computed RoPE frequencies, if you are certain that you won't have to transcribe for more than X hours. By default the model uses a `--max-model-len` of 131072 (> 3h). After serving `vllm`, you should see that the model is compatible with `vllm's` new realtime endpoint: ... (APIServer pid=3246965) INFO 02-03 17:04:43 [launcher.py:58] Route: /v1/realtime, Endpoint: realtime_endpoint ... We have added two simple example files that allow you to: - [Stream audio files](https://docs.vllm.ai/en/latest/examples/online_serving/openai_realtime_client/?h=realtime#openai-realtime-client) - [Simple gradio live transcription demo](https://docs.vllm.ai/en/latest/examples/online_serving/openai_realtime_microphone_client/#openai-realtime-microphone-client) [](https://huggingface.co/spaces/mistralai/Voxtral-Mini-Realtime) **To try out a demo, click [here](https://huggingface.co/spaces/mistralai/Voxtral-Mini-Realtime)** Starting with `transformers >= 5.2.0`, you can run Voxtral Realtime natively in Transformers! For more details, refer to the [Transformers documentation](https://huggingface.co/docs/transformers/main/en/model_doc/voxtral_realtime). Install Transformers: pip install --upgrade transformers Make sure to have `mistral-common` installed with audio dependencies: pip install --upgrade "mistral-common[audio]" from transformers import VoxtralRealtimeForConditionalGeneration, AutoProcessor from mistral_common.tokens.tokenizers.audio import Audio from huggingface_hub import hf_hub_download repo_id = "mistralai/Voxtral-Mini-4B-Realtime-2602" processor = AutoProcessor.from_pretrained(repo_id) model = VoxtralRealtimeForConditionalGeneration.from_pretrained(repo_id, device_map="auto") repo_id = "patrickvonplaten/audio_samples" audio_file = hf_hub_download(repo_id=repo_id, filename="bcn_weather.mp3", repo_type="dataset") audio = Audio.from_file(audio_file, strict=False) audio.resample(processor.feature_extractor.sampling_rate) inputs = processor(audio.audio_array, return_tensors="pt") inputs = inputs.to(model.device, dtype=model.dtype) outputs = model.generate(**inputs) decoded_outputs = processor.batch_decode(outputs, skip_special_tokens=True) print(decoded_outputs[0]) > [!Warning] > Running Voxtral-Realtime on-device with ExecuTorch is not throughly tested and hence > there might be some sharp edges. If you encounter any problems, please file a bug report directly on > [ExecuTorch's GitHub](https://github.com/pytorch/executorch/issues/new/choose) [ExecuTorch](https://github.com/pytorch/executorch) enables you to deploy **Voxtral-Realtime** locally—either on-device or on your laptop. For a quick, offline demo on your MacBook, check out [Voxtral-Mini-4B-Realtime-2602-ExecuTorch](https://huggingface.co/mistral-labs/Voxtral-Mini-4B-Realtime-2602-ExecuTorch). To deploy **Voxtral-Realtime** in a custom environment or on any device, refer to the [Official Readme](https://github.com/pytorch/executorch/blob/main/examples/models/voxtral_realtime/README.md). > [!Tip] > If you're looking for an implementation that is purely written in C, > we recommend to take a look at [voxtral.c](https://github.com/antirez/voxtral.c) Voxtral Realtime integrations in: - [Pure C](https://github.com/antirez/voxtral.c) - thanks [Salvatore Sanfilippo](https://github.com/antirez) - [mlx-audio framework](https://github.com/Blaizzy/mlx-audio) - thanks [Shreyas Karnik](https://github.com/shreyaskarnik) - [MLX](https://github.com/awni/voxmlx) - thanks [Awni Hannun](https://github.com/awni) - [Rust](https://github.com/TrevorS/voxtral-mini-realtime-rs) - thanks [TrevorS](https://github.com/TrevorS) This model is licensed under the [Apache 2.0 License](https://www.apache.org/licenses/LICENSE-2.0.txt). *You must not use this model in a manner that infringes, misappropriates, or otherwise violates any third party’s rights, including intellectual property rights.*