M4A to NIST Converter
Convert M4A audio to NIST speech corpus format
Academic Standard
Convert M4A to NIST format — the standard used by NIST for speech technology evaluation and benchmark datasets.
Online Processing
The conversion runs on our servers. No speech research toolkit installation needed just to produce NIST-compatible audio.
Universal Access
Run the M4A to NIST conversion from any browser — researchers can prepare audio on any platform.
How to convert M4A to NIST
Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.
Choose nist or any other format you need as a result (more than 200 formats supported)
Let the file convert and you can download your nist file right afterwards
About formats
Frequently Asked Questions
NIST is a standard speech audio format used by the National Institute of Standards and Technology for distributing speech evaluation datasets.
NIST and SPH refer to the same SPHERE format. Both names are used interchangeably in the speech research community.
Kaldi, HTK, Praat, and most speech processing frameworks accept NIST/SPHERE audio. Sox can also read and convert it.
NIST is designed for speech research. While it can store any audio, it is optimized for speech recordings with research metadata.
Upload multiple M4A recordings and convert them all to NIST format at once — ideal for assembling speech evaluation datasets.