Montreal Forced Aligner

by MontrealCorpusTools

Word-level alignment via Kaldi for 100+ languages.

Looking at Montreal Forced Aligner? Try this first.

Drop your audio. Transcript in seconds. First transcript free, then $4 = 300 min

TL;DR

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

Category
Open source
License
MIT
Stars
★ 1.9k
Last push
2026-08-07
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

Links

GitHub repo ↗

Montreal Forced Aligner vs Whipscribe

FeatureMontreal Forced AlignerWhipscribe
CategoryOpen sourceTranscription APIs
Pricingfree$4–$24 one-time packs (credits never expire) · $2 single unlock · 60 min free on signup
Speaker diarizationNoYes
Word timestampsYesYes
StreamingNoNo
Languages10099
PlatformsLinux, macOS, WindowsWeb, API, MCP

Alternatives to Montreal Forced Aligner

OpenAI Whisper
OpenAI

The reference open-source multilingual ASR model from OpenAI.

OSS · MIT ★ 107.0k
whisper.cpp
Georgi Gerganov

C/C++ port of Whisper — runs on anything, from a Raspberry Pi to Apple Silicon.

OSS · MIT ★ 52.8k
faster-whisper
SYSTRAN

4× faster than reference Whisper using CTranslate2 — production sweet spot.

OSS · MIT ★ 24.8k

Whipscribe is a managed faster-whisper + whisperX service. If you want transcripts without running infrastructure, paste a URL or drop a file in the form below — you'll have a transcript in seconds.