itch.io

Tune.js (which is a Javascript sound/music generator) has a MIDI to JSON converter on its site which may be helpful.
https://tonejs.github.io/MidiConvert/

Is the limit 1.44 MB (1,440,000 bytes), 1.44 MiB (1,509,949 bytes) or the actual size of a DOS-formatted high density floppy disk (1,474,560 bytes)?