MIDI / Notation Writer
Pick a note length, click cells to place notes across up to four instrument tracks, play it back, and export a real multi-track .mid file. Two octaves, a simple step grid instead of full staff notation.
Last updated
Bars: 1 · Pick a note length above, then click an empty cell to place a note of that length — it automatically stops short of the next note in that row, so notes never overlap. Click any note to remove it.
About this tool
This is a piano-roll style editor, not full staff notation: each row is a pitch (two octaves, C3 to C5 — a comfortable melodic range) and each column is a fixed-length time step, so it can't represent things like key signatures or triplets against a straight grid. Pick a note length from the row above the grid — anywhere from a sixteenth note up to a whole bar, dotted values included — then click an empty cell to place a note of exactly that length. Each note's length is set individually as you place it, not by a single setting for the whole piece.
Up to four instrument tracks play together on the same timeline, each with its own notes and its own instrument — Piano, Flute, Chip Lead, Synth Lead, Electric Bass, Bell, Strings, or Marimba. These are built from oscillator waveforms and shaped envelopes rather than sampled recordings, so they're distinct from each other but not meant to sound fully realistic. A swing control delays every other step for a shuffled, less mechanical feel.
Export .mid writes a real Standard MIDI File built directly in your browser — no library or server involved. Each track gets its own channel and a General MIDI program-change event matching the instrument you picked, so opening the file in a DAW, notation program, or MIDI player carries the instrument choice across, not just the notes. Share / Copy link encodes the whole piece — every track, note, and instrument — into the URL itself, so sending someone the link reproduces it exactly; nothing is uploaded anywhere.
This works the same way on a phone, but a piano-roll editor with several instrument tracks is inherently a lot to navigate through touch and a narrow screen — it's built with a desktop-first layout in mind, where a mouse and a wider window make placing and reviewing notes much easier.