Online MIDI Editor

A piano roll shows time from left to right and pitch from bottom to top, with a keyboard at the left edge. Each note is a bar: its left edge is when it starts, its length is how long it lasts and its row is its pitch. It is the standard way DAWs display and edit MIDI.

Yes. Press Open .mid and choose a Standard MIDI File. Each channel used in each track becomes an editable track with its instrument. Files that change tempo during the song are opened with their first tempo, and the editor tells you when it does this.

Quantize moves note starts to the nearest grid line, for example the nearest 1/16 note, which tightens timing that was played slightly early or late. Tick + lengths to round note lengths to the grid too. With no notes selected the whole current track is quantized.

Velocity is a number from 1 to 127 that tells an instrument how hard a note was played. Higher values usually sound louder and brighter. Drag the bars in the velocity lane, or select notes and press Set to give them the same velocity.

Choose Drum kit (channel 10) as the track's instrument. In General MIDI, drums always use channel 10 and each key is a different drum sound, for example 36 is the kick, 38 the snare and 42 the closed hi-hat. The keyboard shows the drum names.

A MIDI file stores notes, not sound. The editor plays it with a simple built-in synthesizer, while your DAW, keyboard or phone uses its own instrument sounds for the same General MIDI program numbers, so the notes stay the same but the tone changes.

No. Files are read and written entirely in your browser. Your current song is saved only in this browser's local storage so it is still there when you come back.

Yes! Every tool on our site undergoes automated Q/A testing in real browser environments to ensure high precision, correct output, and zero errors. If you happen to spot a bug or have a suggestion, please contact us at [email protected] and our team will review it right away.