Free online SMF to OGG converter

What the SMF format is

SMF means Standard MIDI File. In music composition, an SMF stores musical instructions such as note numbers, timing, velocity, tempo, program changes, controller data, lyrics, and track structure; it does not contain recorded sound. Files commonly use .smf, .mid, or .midi extensions.

Digital audio workstations, notation programs, sequencers, and hardware keyboards create SMF files for exchanging arrangements. A MIDI player interprets those events through a synthesizer or external MIDI device, so the same file can sound different on different systems.

What the OGG format is

OGG is a multimedia container most commonly used with Vorbis-compressed audio, although it can also contain codecs such as Opus. For this conversion, the output is normally an OGG Vorbis audio file containing a rendered performance.

Unlike SMF, OGG contains playable audio rather than editable note events. It is useful for playback, web distribution, and smaller files than uncompressed WAV. OGG is not accepted by every phone, browser, video editor, or hardware player; MP3, AAC, or WAV may be required for broader compatibility.

How to convert SMF to OGG

The conversion has two stages: synthesize the MIDI events into PCM audio, then encode that audio as OGG. A SoundFont or another instrument library is required because the SMF does not provide instrument recordings.

1. Install TiMidity++ and obtain a General MIDI SoundFont, such as a legally distributable .sf2 library.
2. Render the SMF to WAV, specifying the SoundFont if TiMidity++ does not already have a configured default:

   timidity composition.smf -Ow -o rendered.wav

   On installations requiring an explicit SoundFont, use the configuration option provided by that installation, for example:

   timidity -x "soundfont /path/to/GeneralUser.sf2" composition.smf -Ow -o rendered.wav

3. Encode the rendered WAV as OGG Vorbis with FFmpeg:

   ffmpeg -i rendered.wav -c:a libvorbis -q:a 5 composition.ogg

   Values from -q:a 3 to -q:a 6 provide progressively higher quality and larger files; -q:a 5 is a practical starting point.

4. Play composition.ogg and check the beginning, ending, tempo, sustained notes, percussion, and any controller-driven effects. Delete the intermediate WAV only after verifying the OGG file.

For a graphical workflow, import the SMF into MuseScore or a digital audio workstation, select the desired SoundFont or virtual instruments, then use File → Export or the application’s audio-render command to create WAV. Encode that WAV with FFmpeg as above. Exporting directly from a notation or DAW application may preserve its mixer, instrument, and effect settings more accurately than a basic MIDI synthesizer.

You can also use the free converter on the 101convert.com website without installing software: upload the SMF, choose OGG as the output format, start the conversion, and download the rendered file when processing finishes.

Quality and compatibility limits

The SoundFont, synthesizer, effects, channel settings, and tempo interpretation determine the sound; changing the OGG quality setting cannot restore detail that was absent from the chosen MIDI instruments. If the SMF uses custom patches, system-exclusive messages, external hardware, or non-General-MIDI instruments, the rendered result may use incorrect sounds or omit device-specific behavior.

Keep the original SMF for future editing because OGG cannot be converted back into separate notes, tracks, velocities, or controller events. Use WAV instead of OGG when further mixing or mastering is planned, because Vorbis encoding is lossy. Check the target player’s codec support before distributing the file; an OGG container with Vorbis audio is not universally supported.