One voice in, a MIDI file out — monophonic only, so chords and dense mixes will not survive.
Drop a hummed melody, a bass line or a single-note synth take and export a .mid file you can edit. This converter tracks ONE pitch at a time: chords, stacked vocals and full mixes will confuse it, so record each line on its own.
Free · no account · runs in your browser — nothing is uploaded; your audio never leaves your device.
Single voice only — one note at a time. Chords, stacked vocals, drums and dense mixes will not transcribe, and the tool says so instead of guessing. Tempo is yours to set: pitch alone rarely gives a reliable BPM.
Checking the take…
| # | Note | MIDI | Start | Length |
|---|
One line is a sketch. A whole song is a transcription.
SongTranscribe in the studio takes a finished track and gives you MIDI and notation for the parts it can hear — no humming required. Sign up: 3 full packs free.
One line of audio, read as one line of notes
The page decodes the file, then walks the recording frame by frame and asks one question at every frame: what single pitch is here? The tracker is YIN — the autocorrelation family that hardware tuners use — so it locks onto the repeating period of the waveform instead of guessing from loudness. Frames that agree are grouped into a note; a note ends where the pitch moves to a new one, and quiet frames close it out. Those notes become a Standard MIDI File, type 0, one track, with the tempo you set in the field above.
That is the whole machine. No machine learning, no server, no model download. Which also means the limits are physical, not a matter of tuning.
What it cannot do, stated plainly
- One voice only. A chord is several pitches sounding at once and the tracker must return one number per frame, so it picks one and drops the rest — or jumps between them. Stacked vocals and full mixes fail the same way.
- No drums. A drum hit has no pitch to track; a kick or a snare is a burst of noise with a shape, not a fundamental. Percussion comes back as a smear of random notes or nothing at all.
- Reverb, distortion and background noise blur the period the tracker is looking for. The pitch goes unsteady, and unsteady pitch reads as extra notes.
- Wide vibrato can read as a pitch wander, so a long held note with heavy vibrato may split into several small ones.
- Octave errors are the most common mistake. A rich harmonic tone is genuinely ambiguous — the tracker can lock onto half or double the period and be confident about it. Check the octave of the first few notes by ear before you build on the file.
- Short notes can drop out or merge into their neighbour, which is what the “shortest note kept” setting is for.
Tempo, and why you set it
Pitch alone does not tell you the BPM. A melody can be sung at 90 or at 140 and contain the same notes at the same ratios; only the spacing of the note onsets hints at a grid, and a solo line is rarely regular enough to be sure. So the tempo is assumed — 120 BPM by default — unless the note spacing is unusually consistent, and the line under the tempo field always tells you which of the two happened. The MIDI file carries whatever number is in that field, so type the real tempo before you export if you know it: your DAW will line the notes up against its own grid from that value, and a wrong tempo makes every note land in the wrong bar.
Quantise, and the note list
Off keeps the timing exactly as it was played, human drift included — good when you want the performance and will quantise later in the DAW. 1/16 snaps each note's start and length to a sixteenth-note grid at the chosen tempo, which cleans up a sloppy hum but flattens deliberate swing and anything played ahead of or behind the beat. Neither setting invents notes that were not detected; they only move the ones that were.
Under the piano roll the table lists exactly what the file contains: index, note name, MIDI number, start time and length. If a note is in the table it is in the download, and if it is not in the table it is not in the download. Press play to hear those same notes through a plain synth, so you can compare them against the original before you commit them to a part.
What you get, and where it belongs
Download .mid writes a Standard MIDI File straight from your browser. No audio is rendered and nothing is served back — the page has no audio output other than the preview synth, and no file ever leaves the device. There is no upload, no account and no queue.
- A hummed idea into a DAW part. Get the intervals down while the idea is fresh, then give it a real instrument.
- A bass line into a synth. Single-note bass is the easiest material there is for this tracker — clean fundamentals, few overtones in the way.
- A vocal melody to re-voice. Sketch the top line, then hand it to a piano, a string patch or a lead.
Treat the file as a first draft. It is a shortcut past playing the part again, not a transcription service — expect to fix an octave here and there, and to delete the ghost notes that reverb left behind.
Frequently asked questions
What does monophonic mean here?
Monophonic means one pitch at a time. The detector follows a single voice, so a hummed melody or a bass line converts cleanly. A chord is several pitches at once and the converter has to pick one, so the result will be wrong or jumpy. Stacked vocals and full mixes are polyphonic too, and they fail the same way.
What material converts best?
A clean, dry, single-line performance: hummed or sung melody, a bass line, a whistle, or a single-note synth or guitar line. Reverb, distortion and background noise all confuse the pitch tracking, and wide vibrato can read as a wander in pitch. Record close to the mic, one line at a time.
What comes out of it?
A .mid file with note pitches and timings, which you can drop into any DAW and edit, quantize, transpose or re-voice with your own instrument. It is a starting point you fix up, not a finished performance.
How accurate is the pitch tracking?
Good on clean single lines, and wrong in ways you will hear. The most common errors are octave jumps, where a note is read an octave too high or low, and short notes getting dropped or merged. Sing or play through the part, export, and check it by ear against the original before you build on it.