CMU Sphinx-4

by CMU Sphinx

The classic Java speech engine from CMU.

TL;DR

The classic Java speech engine from CMU.

Best for legacy Java systems still on Sphinx. Pricing: free.

Category
Open source
License
—
Stars
—
Last push
—
Pricing
free
Platforms
JVM

What it is

A pure-Java HMM/Gaussian-mixture engine. BSD-2-Clause.

Best for: Legacy Java systems still on Sphinx.
Watch out for: Largely superseded; minimal recent commits.

Install / use

git clone https://github.com/cmusphinx/sphinx4

Features

Speaker diarizationNo
Word-level timestampsYes
Streaming / real-timeYes
Languages supported15
HIPAA eligibleNo

CMU Sphinx-4 vs Whipscribe

FeatureCMU Sphinx-4Whipscribe
CategoryOpen sourceTranscription APIs
Pricingfreefree beta
Speaker diarizationNoYes
Word timestampsYesYes
StreamingYesNo
Languages1599
PlatformsJVMWeb, API, MCP

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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.