MIDI note extractor
Turn a MIDI file into one flat note table — a row per note with pitch, start, duration and velocity — ready to paste into a spreadsheet, pandas or a plotting script. Runs entirely in your browser; nothing is uploaded.
About this tool
MIDI note extractor flattens a Standard MIDI File into a single note table you can drop straight into a spreadsheet, a pandas read_csv, or a plotting script. Paste the .mid/.midi bytes as base64 or hex, pick the columns and the time unit, and every note-on/note-off pair in the file becomes one row: pitch, start, duration and velocity, plus the track and channel it came from.
Everything happens in your browser — the MIDI data is parsed locally by WebAssembly, never uploaded. Note-on and note-off messages are paired per channel and pitch (a note-on with velocity 0 counts as a note-off, as the MIDI spec allows), all tracks are flattened into one table, and rows are sorted by start time unless you ask for track or pitch order.
Choose Minimal columns for the classic four-field note list (start,duration,pitch,velocity), Standard to keep the track, channel and scientific pitch name, or Full to also get the track name, the note end, and the tempo in force when the note starts. Times can be seconds (computed from the file's tempo map, including mid-file tempo changes), raw MIDI ticks, or beats (quarter notes). Velocity can stay the raw 0–127 integer or be normalized to 0.0–1.0 for analysis.
Worked example
The example chips below load a tiny one-note MIDI file: 96 ticks per quarter note, 120 BPM, one track called Piano playing middle C at velocity 64 for one quarter note.
With Standard columns and time in seconds, the result is:
track,channel,start,duration,pitch,note_name,velocity
0,0,0.000,0.500,60,C4,64
Switch the time unit to ticks and the columns to minimal, and the same note becomes:
start,duration,pitch,velocity
0,96,60,64
At 96 ticks per quarter and 120 BPM, a quarter note is 96 ticks and 0.5 seconds — the two views agree.
Limits and edge cases
- The input must be a Standard MIDI File whose first chunk is
MThd(Format 0, 1 or 2). RIFF-wrapped RMID files, sequencer project files, and audio recordings are not decoded. - Up to 50,000 notes are returned. Larger scores can be narrowed with the track or channel filter, or split before extraction.
- Track and channel numbers are 0-based, so channel 9 is the General MIDI drum channel and
0,2selects the first and third tracks. - A note-on that the file never closes with a note-off is held to the end of its track rather than being silently dropped.
- Beats require a metrical (PPQ) file; files using SMPTE timecode division have no musical beat grid, so use seconds or ticks for those.
- Track names containing the delimiter, a double quote, or a newline are quoted RFC 4180 style, so the output stays valid CSV.
- Tick values are always whole numbers; the decimal-places setting applies to seconds, beats, normalized velocity, and tempo.
FAQ
How do I get the base64 or hex text for my .mid file?
Encode the file locally first — base64 song.mid on macOS or Linux, [Convert]::ToBase64String([IO.File]::ReadAllBytes("song.mid")) in PowerShell, or xxd -p song.mid for hex — then paste the text into the input box. Leave the encoding on Auto and the tool works out which one it is. The command-line version accepts the same string.
What exactly do the start and duration columns measure?
start is the note-on position measured from the beginning of the file, and duration is the distance from that note-on to its matching note-off. In seconds both are computed from the file's tempo map, so a tempo change part-way through a note is accounted for. In ticks they are the raw MIDI clock values, and in beats they are quarter notes (ticks divided by the file's ticks-per-quarter).
How are overlapping notes and multiple tracks handled?
Each track is scanned separately and open note-ons are matched to the next note-off with the same channel and pitch, so overlapping or repeated notes pair correctly. All tracks are then flattened into one table with a track column (Standard and Full column sets), and rows are ordered by start time by default. Pick By track, then start time if you would rather keep each track's notes together.
Can I extract just the drums, or just one instrument?
Yes. Set Channels to 9 for the General MIDI drum channel, or Tracks to the 0-based track number that holds the part you want; both fields also accept comma-separated lists such as 0,2. Run once with Full columns to see the track names and channels in the file, then filter.
Does this convert the CSV back into a MIDI file, or play the notes?
No. This tool reads MIDI and writes a note table; it does not write MIDI files and does not synthesize audio. MIDI is symbolic performance data, so what you get is timing and pitch information, not sound.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool midi-note-extract "TVRoZAAAAAYAAAABAGBNVHJr… (or 4d546864000000…)"New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/midi-note-extract/?input=TVRoZAAAAAYAAAABAGBNVHJr%E2%80%A6%20%20%28or%204d546864000000%E2%80%A6%29&encoding=auto&columns=standard&time_unit=seconds&velocity_scale=raw&delimiter=comma&header=true&sort=time&track=all%20%20%28or%200%2C2%29&channel=all%20%20%28or%200%2C9%29&decimals=3Machine-readable descriptor: tool.json — title + parameters JSON Schema for agents.