CC-BY-NC-SA-4.0audioRuns locally3B

Hibiki-Zero: Specs, License & How to Run

Kyutai 3B streaming speech-to-speech (fr/es/pt/de→en). Weights CC-BY-NC-SA-4.0.

Official Hibiki-Zero Temporal Transformer and Depth Transformer architecture figure from the Kyutai paper
Official project image. Source · License: Kyutai paper figure (arXiv:2602.11072).
License
CC-BY-NC-SA-4.0
Parameters
3B
HF likes
59 (2026-10-27)
First seen
2026-02-09

TL;DR. Hibiki-Zero is a audio model from Kyutai. Parameters: 3B.License: CC-BY-NC-SA-4.0. It is listed under DeepL, Otter.ai.

DeveloperKyutai
Typeaudio
ArchitectureDecoder-only hierarchical Transformer (card: 3B backbone) that consumes and emits Mimi audio tokens plus text tokens at 12.5 Hz; audio bitrate 2.2 kbps. config.json model_type hibiki; dim 2048; 28 layers; 16 heads; Depth Transformer 6 layers / dim 1024. Same multistream family as Moshi / Hibiki.
Parameters3B
Modalitiesaudio, speech, text
Languagesfr, es, pt, de, en
LicenseCC-BY-NC-SA-4.0 — The lead card README states “License: CC BY-NC-SA 4.0” (opened 2026-10-27). Hugging Face cardData.license is empty and the card siblings list has no LICENSE blob. The inference repo kyutai-labs/hibiki-zero is MIT (GitHub license API + LICENSE file). Do not flatten weights and code into one SPDX. CC BY-NC-SA 4.0 is attribution + non-commercial + share-alike. Not commercial-free. Not legal advice.
Hardware8 GB (vendor README; 12 GB “safe”) — GitHub README: NVIDIA GPU; “8 GB VRAM should work, 12 GB is safe.” Card: batched inference 3× faster than real-time on a single H100 (vendor). HF usedStorage 6,648,922,558 bytes (~6.19 GiB). Peak VRAM is not independently measured. Python >=3.10,<3.14 (pyproject.toml 0.0.4). (not independently tested)
Hugging Face likes59 (as of 2026-10-27)
Model cardhttps://huggingface.co/kyutai/hibiki-zero-3b-pytorch-bf16
First seen2026-02-09

Hibiki-Zero is Kyutai’s open simultaneous speech-to-speech checkpoint: a 3B hierarchical Transformer plus a hibiki-zero inference server. Official hosts we opened on 2026-10-27: kyutai/hibiki-zero-3b-pytorch-bf16 (the card the README and GitHub call “Hibiki-Zero”), github.com/kyutai-labs/hibiki-zero (278 stars; MIT), the blog Hibiki-Zero: Simultaneous Speech-to-Speech Translation Without Aligned Data (12 February 2026), and arXiv:2602.11072. This is Kyutai’s own lead card, not a community fine-tune.

This page hangs off DeepL alternatives (self-hosted translation search) and Otter.ai alternatives (live-speech search). Those mappings are editorial. DeepL is hosted text MT. Otter is a meeting-notes product. Hibiki-Zero is streaming speech-to-speech from French, Spanish, Portuguese, and German into English. We do not rank quality against DeepL, Otter, Interprefy, KUDO, or human interpreters.

Same-site speech peers: Hy-SimulMT (Tencent Hunyuan 30B-A3B simultaneous Chinese–English) — Hibiki-Zero vs Hy-SimulMT — and Granite Speech 5.0 (IBM file ASR/AST).

What the card says it does

Copied labels from the README we opened: simultaneous speech translation without word-level alignments; {French, Spanish, Portuguese, German}-to-English; real-time speech and timestamped text; voice transfer; temperature sampling (batch-friendly); trained on sequences up to 120 seconds; one speaker and one language per session, with a claimed zero-shot multi-speaker / mixed-language capability. Speech output is in-model (Mimi tokens) — not an optional external TTS service. Those sentences are upstream.

Hugging Face cardData.language is fr, es, pt, de, en. That matches the prose. The blog/paper’s Italian adaptation (<1000 h) is not a shipped pair on this card.

How it differs from Hy-SimulMT and Granite Speech 5.0

Field Hibiki-Zero Hy-SimulMT Granite Speech 5.0
Job Streaming S2ST + text Streaming S2ST + text (SimulInfer) File ASR / bidirectional AST
Pairs (prose) fr/es/pt/de → en zh ↔ en Six-language ASR; AST to/from English
Size 3B (card) 30B-A3B ~2.3B (5.0-2B)
Weights license CC BY-NC-SA 4.0 (README) Apache-2.0 Apache-2.0 (card tag)
Voice Built-in transfer (card) Optional configured TTS No speech-out on the 5.0-2B card

This table is identification. We have no sourced bake-off. See Hibiki-Zero vs Hy-SimulMT and Hy-SimulMT vs Granite Speech 5.0.

What we verified (2026-10-27)

Field Value Source
HF likes / downloads 59 / 3,251 HF API kyutai/hibiki-zero-3b-pytorch-bf16
Card created / last modified 2026-02-09T15:58:50Z / 2026-02-12T15:35:39Z same
Gated false HF API
License (README body) CC BY-NC-SA 4.0 HF README
License (cardData) empty HF API
LICENSE blob on card none HF siblings
Pipeline tag audio-to-audio HF API / YAML
Config model_type: hibiki; dim 2048; 28 layers HF config.json
usedStorage 6,648,922,558 bytes (~6.19 GiB) HF API
GitHub stars / forks 278 / 25 GitHub API
GitHub created / last push 2026-02-09T15:29:05Z / 2026-09-09T14:36:54Z same
GitHub license MIT GitHub API + LICENSE
Language Python GitHub API
Package version 0.0.4 (>=3.10,<3.14) pyproject.toml
Blog date 12 February 2026 kyutai.org

How to run (from official README, not yet tested)

The GitHub README’s one-command path:

uvx -p 3.13 hibiki-zero serve

Then open the URL it prints. --gradio-tunnel is documented for a public tunnel. Without uv: pip install hibiki-zero then hibiki-zero serve. File / batch path: hibiki-zero generate --file /path/to/audio.wav. NVIDIA GPU required. forkalt has not run those commands.

License

Weights: the card README we opened says CC BY-NC-SA 4.0. Hugging Face cardData.license was empty. There is no LICENSE file among the six card siblings. Read CC BY-NC-SA 4.0.

Code: kyutai-labs/hibiki-zero/LICENSE is MIT (“Copyright (c) 2026 kyutai”). GitHub’s license API agrees.

Do not treat MIT inference code as a commercial grant on the 3B weights. Not legal advice.

What we did not verify

Vendor BLEU / ASR-BLEU / speaker-similarity / average-lag rows on the Kyutai blog stay self-reported. Subjective audio-quality tables stay vendor. The H100 “3× faster than real-time” sentence is upstream. Peak VRAM, live lag on our hardware, and Italian as a shipped pair are not filled in with guesses.

Related: Hy-SimulMT — Hibiki-Zero vs Hy-SimulMT, Granite Speech 5.0 — Hy-SimulMT vs Granite Speech 5.0, Nemotron 3.5 Transcribe (file ASR, not streaming S2ST) — Nemotron 3.5 Transcribe vs Granite Speech 5.0, LibreTranslate (text MT API), whisper.cpp, DeepL alternatives, Otter.ai alternatives.

Benchmarks

Quoted from the cited source. forkalt has not independently reproduced these numbers.

NameScoreSource
Fr→En BLEU (vendor blog)30.6 (self-reported)https://kyutai.org/blog/2026-02-12-hibiki-zero/
Fr→En avg. lag seconds (vendor blog)6.1 (self-reported)https://kyutai.org/blog/2026-02-12-hibiki-zero/
Es→En BLEU (vendor blog)32.3 (self-reported)https://kyutai.org/blog/2026-02-12-hibiki-zero/

Deploy options

Comparisons

FAQ

Is Hibiki-Zero an official Kyutai model?

Yes. The ungated lead card is huggingface.co/kyutai/hibiki-zero-3b-pytorch-bf16 (created 2026-02-09T15:58:50Z). Inference code is github.com/kyutai-labs/hibiki-zero (created 2026-02-09T15:29:05Z). The 12 February 2026 Kyutai blog names the same ids. It is not a third-party fine-tune.

Are the weights open for commercial use?

The card README says CC BY-NC-SA 4.0. That is a non-commercial, share-alike grant. Hugging Face cardData.license was empty in the 2026-10-27 API check and the card has no LICENSE file. The GitHub inference repo is MIT. Do not treat the MIT code license as a weight grant. Not legal advice.

Does it replace DeepL, Otter, or Hy-SimulMT?

No. DeepL is hosted text MT. Otter is a meeting-notes product. Hibiki-Zero is a local streaming speech-to-speech checkpoint (French, Spanish, Portuguese, German → English) with built-in voice transfer. Hy-SimulMT is Tencent Hunyuan’s Apache-2.0 30B-A3B simultaneous Chinese–English stack. Different pairs, size, and license. We have no sourced bake-off.

Which languages are actually shipped?

Card and blog: French, Spanish, Portuguese, and German into English. One speaker and one language per session. The blog/paper mention an Italian adaptation with less than 1000 hours as a research result — Italian is not in Hugging Face cardData.language and is not listed as a shipped pair here.

Sources & verification

Last verified 2026-10-27 · Last updated 2026-10-27· Edited by forkalt editors · Editorial policy

License notes are not legal advice. Read the original LICENSE. Trademark & disclaimer.