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NIST File - What is a .nist file and how do I open it?
Learn about .NIST files and view a list of programs that open them.
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Overview
What is a NIST file? A NIST file is a waveform audio file saved in the National Institute of Standards and Technology's Speech Header Resources (SPHERE) format, which is used in speech recognition research. It contains a recording of a person speaking. NIST files are used as input for speech recognition systems, such as the Hidden Markov Model Toolkit (HTK).
More Information In 1991, the National Institute of Standards and Technology (NIST) developed a standard audio format that could be used to save and distribute files meant to be used with speech recognition research software. This format was called NIST SPHERE, and files saved in this format were often saved with the .nist extension. Notably, NIST files all include a standard ASCII header that specifies numerous pieces of metadata , including the files' database type, database version, number of audio channels, number of audio samples, and sample rate. NOTE: NIST files are sometimes saved with the .SPH extension.
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.NIST File Extension
2 file types use the .nist file extension.
NIST SPHERE Audio File
| Developer | NIST |
| Popularity |
1.5 | 2 Votes |
NEW: Open your .NIST file online with File Helper . View Online
What is a NIST file?
A NIST file is a waveform audio file saved in the National Institute of Standards and Technology's Speech Header Resources (SPHERE) format, which is used in speech recognition research. It contains a recording of a person speaking. NIST files are used as input for speech recognition systems, such as the Hidden Markov Model Toolkit (HTK).
More Information
In 1991, the National Institute of Standards and Technology (NIST) developed a standard audio format that could be used to save and distribute files meant to be used with speech recognition research software. This format was called NIST SPHERE, and files saved in this format were often saved with the .nist extension.
Notably, NIST files all include a standard ASCII header that specifies numerous pieces of metadata , including the files' database type, database version, number of audio channels, number of audio samples, and sample rate.
NOTE: NIST files are sometimes saved with the .SPH extension.
How to open a NIST file
Because NIST files are uncommon, most popular media players cannot play them. However, you can play NIST audio in VLC media player , and you can convert NIST files to a more usable audio format using FFmpeg or SoX .
Programs that open NIST files
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Platform
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X
Windows
File Viewer Plus
—
Get it from Microsoft
Free +
VideoLAN VLC media player
Free
SoX
Free
FFmpeg
Free
Mac
VideoLAN VLC media player
Free
SoX
Free
FFmpeg
Free
Linux
VideoLAN VLC media player
Free
SoX
Free
FFmpeg
Free
Web
FileHelper.com
Free
Category: Audio Files
Updated: September 15, 2020
NIST Biometric Data File
| Developer | NIST |
| Popularity |
2.0 | 1 Vote |
A NIST file may also be a biometric data file that stores fingerprints, facial images, and other related personal information in a standardized format developed by the National Institute of Standards and Technology (NIST). It may contain multiple biometric images, such as rolled or flat fingerprints, along with identification information, capture details, and system metadata . NIST files ensure that users can share and accurately open biometric information across systems and organizations.
More Information
Law enforcement, forensic laboratories, and government agencies may use NIST files to manage and exchange biometric records. Software that processes NIST files can extract, match, and analyze this data, allowing agencies to perform identity verification, background checks, and criminal investigations.
NOTE: NIST files are closely related to .EFT and .NST files, as all three store fingerprint or biometric data, following similar standards for secure exchange and system compatibility.
How to open a NIST file
You can open NIST files with NIST Biometric Image Software or Net-X Solutions NIST Viewer in Windows. To open a NIST file with the app, select File → Open .
Programs that open NIST files
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NIST Biometric Image Software
Free
Net-X Solutions NIST Viewer
Free
Category: Data Files
Updated: November 5, 2025