Montreal Forced Aligner

by MontrealCorpusTools

Word-level alignment via Kaldi for 100+ languages.

TL;DR

Word-level alignment via Kaldi for 100+ languages.

Best for linguists + TTS data prep needing phoneme-level alignments. Pricing: free.

Category
Open source
License
—
Stars
—
Last push
—
Pricing
free
Platforms
Linux, macOS, Windows

What it is

The standard tool for forced alignment in academic linguistics. MIT.

Best for: Linguists + TTS data prep needing phoneme-level alignments.
Watch out for: Not for free-form transcription; needs text + audio + pron dict.

Install / use

conda install -c conda-forge montreal-forced-aligner

Features

Speaker diarizationNo
Word-level timestampsYes
Streaming / real-timeNo
Languages supported100
HIPAA eligibleNo

Montreal Forced Aligner vs Whipscribe

FeatureMontreal Forced AlignerWhipscribe
CategoryOpen sourceTranscription APIs
Pricingfreefree beta
Speaker diarizationNoYes
Word timestampsYesYes
StreamingNoNo
Languages10099
PlatformsLinux, macOS, WindowsWeb, API, MCP

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