Model reference · open weights

MegaTTS3

Available as managed deployment Audio ByteDance Text→speech 1 variants 566 dl/mo

MegaTTS3 is an open-weight audio or speech model from ByteDance. AxForge deploys and operates it for you on dedicated EU-owned hardware — with the licence handled where one is required.

Available as managed deployment — configured and operated for you on dedicated EU hardware, quoted per deployment.

What it is

Released byByteDance
TypeAudio & music
TaskText→speech
Released2025-03-28
Popularity566 downloads / month
LicenceOpen weights

About

What MegaTTS3 is

This is a huggingface model card for MegaTTS 3 👋

Read the full model card

Installation

# Clone the repository
git clone https://github.com/bytedance/MegaTTS3
cd MegaTTS3

Model Download

huggingface-cli download ByteDance/MegaTTS3 --local-dir ./checkpoints --local-dir-use-symlinks False

Requirements (for Linux)

# Create a python 3.10 conda env (you could also use virtualenv)
conda create -n megatts3-env python=3.10
conda activate megatts3-env
pip install -r requirements.txt

# Set the root directory
export PYTHONPATH="/path/to/MegaTTS3:$PYTHONPATH"

# [Optional] Set GPU
export CUDA_VISIBLE_DEVICES=0

# If you encounter bugs with pydantic in inference, you should check if the versions of pydantic and gradio are matched.
# [Note] if you encounter bugs related with httpx, please check that whether your environmental variable "no_proxy" has patterns like "::"

Requirements (for Windows)

# [The Windows version is currently under testing]
# Comment below dependence in requirements.txt:
# # WeTextProcessing==1.0.4.1

# Create a python 3.10 conda env (you could also use virtualenv)
conda create -n megatts3-env python=3.10
conda activate megatts3-env
pip install -r requirements.txt
conda install -y -c conda-forge pynini==2.1.5
pip install WeTextProcessing==1.0.3

# [Optional] If you want GPU inference, you may need to install specific version of PyTorch for your GPU from https://pytorch.org/.
pip3 install torch torchvision torchaudio --index-url https://download.pytorch.org/whl/cu126

# [Note] if you encounter bugs related with `ffprobe` or `ffmpeg`, you can install it through `conda install -c conda-forge ffmpeg`

# Set environment variable for root directory
set PYTHONPATH="C:\path\to\MegaTTS3;%PYTHONPATH%" # Windows
$env:PYTHONPATH="C:\path\to\MegaTTS3;%PYTHONPATH%" # Powershell on Windows
conda env config vars set PYTHONPATH="C:\path\to\MegaTTS3;%PYTHONPATH%" # For conda users

# [Optional] Set GPU
set CUDA_VISIBLE_DEVICES=0 # Windows
$env:CUDA_VISIBLE_DEVICES=0 # Powershell on Windows

Requirements (for Docker)

# [The Docker version is currently under testing]
# ! You should download the pretrained checkpoint before running the following command
docker build . -t megatts3:latest

# For GPU inference
docker run -it -p 7929:7929 --gpus all -e CUDA_VISIBLE_DEVICES=0 megatts3:latest
# For CPU inference
docker run -it -p 7929:7929  megatts3:latest

# Visit http://0.0.0.0:7929/ for gradio.

[!TIP] [IMPORTANT] For security issues, we do not upload the parameters of WaveVAE encoder to the above links. You can only use the pre-extracted latents from link1 for inference. If you want to synthesize speech for speaker A, you need "A.wav" and "A.npy" in the same directory. If you have any questions or suggestions for our model, please email us.

This project is primarily intended for academic purposes. For academic datasets requiring evaluation, you may upload them to the voice request queue in link2 (within 24s for each clip). After verifying that your uploaded voices are free from safety issues, we will upload their latent files to link1 as soon as possible.

In the coming days, we will also prepare and release the latent representations for some common TTS benchmarks.

Inference

Command-Line Usage (Standard)

# p_w (intelligibility weight), t_w (similarity weight). Typically, prompt with more noises requires higher p_w and t_w
python tts/infer_cli.py --input_wav 'assets/Chinese_prompt.wav'  --input_text "另一边的桌上,一位读书人嗤之以鼻道,'佛子三藏,神子燕小鱼是什么样的人物,李家的那个李子夜如何与他们相提并论?'" --output_dir ./gen

# As long as audio volume and pronunciation are appropriate, increasing --t_w within reasonable ranges (2.0~5.0)
# will increase the generated speech's expressiveness and similarity (especially for some emotional cases).
python tts/infer_cli.py --input_wav 'assets/English_prompt.wav' --input_text 'As his long promised tariff threat turned into reality this week, top human advisers began fielding a wave of calls from business leaders, particularly in the automotive sector, along with lawmakers who were sounding the alarm.' --output_dir ./gen --p_w 2.0 --t_w 3.0

Command-Line Usage (for TTS with Accents)

# When p_w (intelligibility weight) ≈ 1.0, the generated audio closely retains the speaker’s original accent. As p_w increases, it shifts toward standard pronunciation.
# t_w (similarity weight) is typically set 0–3 points higher than p_w for optimal results.
# Useful for accented TTS or solving the accent problems in cross-lingual TTS.
python tts/infer_cli.py --input_wav 'assets/English_prompt.wav' --input_text '这是一条有口音的音频。' --output_dir ./gen --p_w 1.0 --t_w 3.0

python tts/infer_cli.py --input_wav 'assets/English_prompt.wav' --input_text '这条音频的发音标准一些了吗?' --output_dir ./gen --p_w 2.5 --t_w 2.5

Web UI Usage

# We also support cpu inference, but it may take about 30 seconds (for 10 inference steps).
python tts/gradio_api.py

Security

If you discover a potential security issue in this project, or think you may have discovered a security issue, we ask that you notify Bytedance Security via our security center or sec@bytedance.com.

Please do not create a public issue.

License

This project is licensed under the [Apache-2.0

From the published model card. Full card on the HuggingFace links in the sidebar.

How it works

How audio & music work

Audio or textinputAudio modelrecognise / synthesiseText or audiooutputSpeech-to-text turns audio into text; text-to-speech and music models turn text into audio.

Using it via the API

Call it like any OpenAI endpoint

Once AxForge deploys megatts3 for you, it answers on the OpenAI-compatible API — the same base URL and keys as every other model. (megatts3 below is illustrative; you get the exact model name on deployment.)

$ curl -sS https://api.axforge.ai/v1/audio/transcriptions \
  -H "Authorization: Bearer $AXFORGE_API_KEY" \
  -F model="megatts3" -F file=@audio.mp3

Create an account — your API key is available in the console. 3M free tokens every 30 days with every new account.

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