How to Convert Audio to MIDI in Your Browser (Hum a Melody, Get Notes)

The melody is in your head and you hum it into your phone — but a voice memo isn't something a synth can play. Audio to MIDI bridges that gap. Drop in a recording of a hummed tune, a guitar riff, a bassline, or a synth take, and it transcribes the pitches into editable MIDI notes you can tweak, re-voice with any instrument, and export to any DAW. All in your browser, free, with nothing uploaded.

Here's how to use it, which engine to pick, and how to get a clean result.

#What "audio to MIDI" actually means

Audio is a recording of a sound. MIDI is the notes — the instructions for which pitch plays, when, and how hard. Converting audio to MIDI means listening to your recording, working out the notes you played, and writing them down as data you can edit.

Once your performance is MIDI, you're free: play it back with a piano, a string section, an 808, or any synth; fix a wrong note; quantize the timing; transpose it to another key. The performance becomes raw, malleable material instead of a fixed waveform.

It runs entirely on your device — your audio never leaves the browser, which makes it private and free, with no per-conversion cost.

#Pick the right engine: Melody vs. Polyphonic

Audio to MIDI gives you two transcription engines, and choosing correctly is the difference between a clean result and a mess.

• Melody is for one note at a time — a single melodic line. A hummed tune, a sung melody, a bassline, a lead synth, a solo. It tracks that single pitch as it moves, and it's reliable and fast.
• Polyphonic is for multiple notes at once — chords, piano, fingerpicked or strummed guitar. It runs a neural model (Spotify's Basic Pitch) right in your browser to pull apart simultaneous notes.

The rule of thumb: if you're transcribing a single line, use Melody. If you're transcribing harmony, use Polyphonic. And whichever you pick, the cleaner and more isolated the source, the better the result.

#Step by step

1. Load your audio. Drop in your recording (a hum, riff, bassline, or take). Most common formats work.
2. Choose the engine. Melody for a single line; Polyphonic for chords and harmonic instruments.
3. Transcribe. Run it and the tool analyzes the audio and detects the notes — locally, in the browser.
4. Review on the piano roll. Your transcription appears as note blocks on a piano roll, and you can play it back with a synth voice to hear what it caught.
5. Clean it up. Drag notes to fix pitch, trim or extend their lengths, delete stray notes the detector imagined, and add any it missed.
6. Export the .mid — or send it onward.

#Get a cleaner transcription

No pitch detector is perfect, and a hum full of slides and breaths gives it a workout. A few habits dramatically improve the result:

• Perform clearly and in tune. Crisp, deliberate notes transcribe far better than mumbled, sliding ones. Sing or play like you mean it.
• Isolate the source. Dry and solo'd beats a recording with reverb, backing, or room noise. Less for the detector to second-guess.
• Match the engine to the material. Running Polyphonic on a single line, or Melody on a chord, fights the tool. Pick the right one.
• Expect to edit. Treat the output as a strong first draft. A minute of nudging notes on the piano roll turns a good transcription into an accurate one.

#Where to take the MIDI

The value of MIDI is what you do next:

• Export a .mid file and drop it into any DAW — Onomo's Studio or anything else — to trigger your own instruments.
• Re-voice it. That hummed melody can become a supersaw lead, a piano, or a flute. Same notes, completely different sound.
• Build on it. Transcribe a bassline, then write a counter-melody over it; or grab the chords from a song and reharmonize.

A captured idea you can edit is worth far more than a voice memo you can only replay.

#FAQ

Is Audio to MIDI free? Yes — both engines run in your browser, free, with nothing uploaded.

Can it convert a whole song to MIDI? It works best on one instrument at a time, not a full mix. To transcribe one part of a finished track, isolate it with the Stem Splitter first, then convert that stem.

Which engine should I use to transcribe chords? Polyphonic — it's built for multiple simultaneous notes. Use Melody for single lines.

Will the result be perfect? Think of it as an editable first draft. It captures the notes well, and the built-in piano roll lets you quickly fix anything it got wrong.

Does it work on my phone? It runs in a mobile browser, though editing notes on the piano roll is easier on a larger screen.

#Turn your hum into notes

Open Audio to MIDI, drop in that melody you've been humming, pick Melody or Polyphonic, and transcribe. Tidy it up on the piano roll, export the .mid, and finally play your idea with any instrument you want.