NIST SPHERE is the standard format of speech corpora — every academic speech-recognition dataset (TIMIT, Switchboard) ships thousands of .sph files with ASCII headers.
Typical use: Convert SPHERE speech corpora to WAV for ML pipelines.
About the NIST format
NIST SPHERE is the standard format of speech corpora — every academic speech-recognition dataset (TIMIT, Switchboard) ships thousands of .sph files with ASCII headers.
ffmpeg decodes it natively inside your browser — the audio track is re-encoded to your chosen format with nothing ever uploaded.
Strengths
- ✓ Decoded natively by ffmpeg
- ✓ Runs entirely in your browser
- ✓ Free, private, no watermarks
Limitations
- ✗ Legacy niche format
- ✗ Modern tools rarely open it
- ✗ Keep the original for archival round-trips
- Structure
- NIST SPHERE Speech container
- Compatibility
- ffmpeg, archive tools
- Best for
- Rescuing legacy audio
Convert NIST to…
0 direct directions, sorted A–Z; 🔥 marks popular targets.
Frequently asked questions
What is a NIST file?
NIST SPHERE is the standard format of speech corpora — every academic speech-recognition dataset (TIMIT, Switchboard) ships thousands of .sph files with ASCII headers.
How do I convert NIST files online?
Pick a target format from the "Convert NIST to…" list below, drop your file and hit convert. Everything runs in your browser — no install, no upload, no watermark, no limits.
Is it safe to convert NIST files here?
Yes. Every conversion is performed by your own device inside the browser — files never leave for a server, and the page keeps working even offline.
Which formats can NIST convert to?
This page lists all 0 directions across documents, images, audio, video, spreadsheets and archives — each one is its own free converter page.