HTK mel-frequency cepstral coefficient data
File type: Various data file
An mfcc file is an HTK feature-data file containing mel-frequency cepstral coefficient (MFCC) data.
It stores speech features for use in Hidden Markov Model Toolkit (HTK) speech-recognition and analysis workflows.
File type category:
Various data file
Date updated: October 17, 2026
The mfcc file extension is associated with the Hidden Markov Model Toolkit (HTK), a toolkit for building and working with hidden Markov models. HTK is available for Microsoft Windows and Linux.
The mfcc file contains a sequence of MFCC feature vectors, normally representing short frames of analyzed speech. HTK feature files include information that describes the stored parameters, such as the number of samples, the sample size, and the parameter kind.
MFCC files are intermediate or input data for HTK speech-recognition systems rather than general-purpose audio files. They remain useful in HTK-based speech research and applications, although the format is specialized and intended primarily for compatibility with HTK tools.
Use the Hidden Markov Model Toolkit on Windows or Linux to process an mfcc file. HTK's HList utility can display the contents of HTK parameter files, while other HTK tools can use the data in recognition and model-building workflows.
The file is not intended to be opened as audio in a media player or general-purpose document viewer.
An mfcc file is already extracted feature data, so it has no useful generic conversion to an audio format. A program that understands HTK parameter files is required to interpret the data.
HTK's HCopy utility can extract MFCC features from suitable source speech files or convert compatible HTK parameter data when configured to do so. Recreating the file from audio generally requires the original speech source and the desired HTK feature settings.
Software applications that can open mfcc files:
Microsoft Windows
Software apps that create mfcc files:
Microsoft Windows
Software applications that handle other tasks involving mfcc files:
Microsoft Windows
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