VMS is the cropped ADPCM dialect used by answering machines and dictation recorders — dialects of Dallas Semiconductor's timekeeping chips.
Typical use: Convert VMS voice messages to WAV or MP3.
About the VMS format
FSSD is a raw 8-bit audio dump format from early UNIX sound experiments — tiny headers, bare samples.
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
- Voice Mail System container
- Compatibility
- ffmpeg, archive tools
- Best for
- Rescuing legacy audio
Convert VMS to…
27 direct directions plus 18 workflows, sorted A–Z; 🔥 marks popular targets.
Frequently asked questions
What is a VMS file?
VMS is the cropped ADPCM dialect used by answering machines and dictation recorders — dialects of Dallas Semiconductor's timekeeping chips.
How do I convert VMS files online?
Pick a target format from the "Convert VMS 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 VMS 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 VMS convert to?
This page lists all 45 directions across documents, images, audio, video, spreadsheets and archives — each one is its own free converter page.