Quantize MIDI without flattening the whole performance
Select a MIDI passage, choose a 1/4 to 1/32 grid, quantize note starts, preview the change, undo mistakes, and export a new MIDI file.
Last updated September 2, 20261. Open the file in the local Editor
Open the online MIDI Editor and choose one `.mid` or `.midi` file. The file remains in browser memory throughout editing and export.
2. Select only the notes that need correction
Click one note, hold Ctrl or Command to build a selection, drag a box around a phrase, or use Select all. Quantize is disabled until at least one note is selected.
3. Pick a useful grid
Use 1/4 for broad beat alignment, 1/8 for common accompaniment patterns, 1/16 for tighter melodic or drum work, and 1/32 only when the source really contains that detail.
4. Apply, listen, and undo when needed
The Editor moves selected note starts to the nearest grid point and preserves their durations. Preview the updated file. If the phrase feels too rigid, Undo and choose a wider grid or a smaller selection.
5. Download the corrected MIDI
Download creates a new `-edited.mid` file. The original file on your device is not overwritten. Use the MIDI Player for longer practice sessions or the MIDI Converter when you need shareable audio.