Montreal Forced Aligner
The Montreal Forced Aligner is a command line utility for performing forced alignment of speech datasets using Kaldi (http://kaldi-asr.org/).
Please see the documentation http://montreal-forced-aligner.readthedocs.io for installation and usage.
If you run into any issues, please check the mailing list for fixes/workarounds or to post a new issue.
Citation
MFA 3.0
For citing the latest version of MFA and its pretrained models, please use:
McAuliffe, Michael, Kaylynn Gunter, Michael Wagner, and Morgan Sonderegger (2026). Montreal Forced Aligner and the state of speech-to-text alignment in 2026. In Proceedings of Interspeech 2026.
@inproceedings{mcauliffe26_interspeech,
author={McAuliffe, Michael and Gunter, Kaylynn and Wagner, Michael and Sonderegger, Morgan},
title={{Montreal Forced Aligner and the state of speech-to-text alignment in 2026}},
year=2026,
booktitle={Proc. Interspeech 2026}
}
MFA 1.0
For citing the original software and models (upgrading to the MFA 3.X is recommended!), please use:
McAuliffe, Michael, Michaela Socolof, Sarah Mihuc, Michael Wagner, and Morgan Sonderegger (2017). Montreal Forced Aligner: trainable text-speech alignment using Kaldi. In Proceedings of Interspeech 2017.
@inproceedings{mcauliffe17_interspeech,
author={McAuliffe, Michael and Socolof, Michaela and Mihuc, Sarah and Wagner, Michael and Sonderegger, Morgan},
title={{Montreal Forced Aligner: Trainable Text-Speech Alignment Using Kaldi}},
year=2017,
booktitle={Proc. Interspeech 2017},
pages={498--502},
doi={10.21437/Interspeech.2017-1386}
}
Installation
You can install MFA either entirely through conda or a mix of conda for Kaldi and Pynini dependencies and Python packaging for MFA itself
Conda installation
MFA is hosted on conda-forge and can be installed via:
conda install -c conda-forge montreal-forced-aligner
in your environment of choice.
Source installation
If you'd like to install a local version of MFA or want to use the development set up, the easiest way is first create the dev environment from the yaml in the repo root directory:
conda env create -n mfa-dev -f environment.yml
Alternatively, the dependencies can be installed via:
conda install -c conda-forge python=3.11 kaldi librosa praatio tqdm requests colorama pyyaml pynini openfst baumwelch ngram
MFA can be installed in develop mode via:
pip install -e .[dev]
You should be able to see appropriate output from mfa version
Development
The test suite is run via tox -e py38-win or tox -e py38-unix depending on the OS, and the docs are generated via tox -e docs
Quick links
1 maintainer
Metadata
1 maintainer
Release files for Montreal-Forced-Aligner 3.4.3
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Source distribution (sdist)
| File | Size | Uploaded | |
|---|---|---|---|
| montreal_forced_aligner-3.4.3.tar.gz | 27.0 MB | Details |
Built distribution (wheel)
| File | Interpreter | ABI | Platform | Reset |
|---|---|---|---|---|
| montreal_forced_aligner-3.4.3-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 27.5 MB
Release files / montreal_forced_aligner-3.4.3.tar.gz
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| Size | 27.0 MB |
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