What is a .MO3 file?
MO3 is a compressed tracker-module format that stores a MOD/XM/IT/S3M song’s samples as MP3 or Ogg Vorbis to shrink the file. Used widely in the demoscene.
- Did you know
- MO3 kept the tracker patterns intact but compressed the bulky samples, often roughly halving a module’s size.
- MO3 comes from Un4seen, the makers of the XMPlay player and BASS audio library, where it remains a natively supported format.
- Because it re-encodes the samples as MP3 or Ogg Vorbis, MO3 is technically lossy even though the song's pattern data is preserved exactly.
- What Analyser shows you
- Play and analyse tracker modules - MOD, XM, IT, S3M and around sixty relatives from the demoscene and the Amiga and DOS eras. A module is not recorded audio: it is a bank of instrument samples plus a pattern score saying which sample to trigger, on which channel, at which row, so playing one means running a tracker engine. Analyser renders the song on your device with libopenmpt - the engine behind OpenMPT - and then treats the result like any other audio, so you get the full Sound section: waveform, spectrogram, transport, loudness, key and BPM. Above it sits the module itself - the tracker that wrote it, the channel, pattern and order counts, the song message, and the sample and instrument name lists, which is traditionally where authors left their greetings. The rendered song can be saved as a WAV.
- Open a .MO3 file
- Drag a .MO3 file onto the Analyser home page (or tap to pick one). It opens entirely in your browser - nothing is uploaded, there is no account, and it works offline once installed.