Convert a local guitar recording into one downloadable MIDI note track. Free, no sign-up. Accepts MP3, WAV, M4A, FLAC and OGG up to 100 MB or 10 minutes. Two CC0 guitar recordings we ran through this page produced 51 and 86 notes in a single track.
Conversion runs entirely in your browser. Your audio is not uploaded to any server.
On October 26, 2026, we selected two CC0 guitar recordings in the live browser converter, downloaded each .mid file and read the downloads with an independent MIDI parser. Both results contain one note-bearing track. These are output counts from one Windows computer, not accuracy scores or speed promises.
Both clips are short, so the note count is dense relative to the playing time. We had no aligned score and no correct MIDI for either recording. The short notes and the extra pitches are therefore items to inspect, not confirmed errors, and we do not publish an accuracy percentage for guitar input.
The guitar-1.wav result contains exactly one note at MIDI pitch 28, which is 41.2 Hz. A six-string guitar in standard tuning cannot play that note: its lowest open string is E2, MIDI 40, at 82.4 Hz. So we checked the recording instead of assuming either answer.
In the 0.35-second window where that note appears (1.60–1.95 seconds), the recording's energy at 41.2 Hz is 27.1 dB below its energy at 82.4 Hz, and only 7.4 dB above the local noise floor measured across 50–70 Hz. The strongest low-frequency peak in that window is 123.5 Hz (B2), and 82.4 Hz (E2) is present 34.6 dB above that noise floor. Across the whole clip, 41.2 Hz sits 5.6 dB below the noise floor. The recording contains no sustained 41.2 Hz fundamental.
The source is therefore not a low-tuned or down-octave guitar. This is an octave error: the converter reported the same E2 moment twice, once an octave too low. In this clip it happened once, next to a correctly reported pitch 40 at the same 1.649-second onset. We have measured only two guitar clips, so we cannot state how often it happens elsewhere; a single occurrence in a 2.9-second file is what we observed, not a rate.
What would settle the rate: a guitar recording whose lowest played note is known in advance, with a matching score or tablature, so every output note can be checked against a known pitch. Neither of our two clips has that reference. The check above is a single-frequency energy comparison on the source WAV, and it can be repeated on any recording without the model.
Choose a local guitar recording above and convert it. The audio is decoded in your browser, resampled to 22,050 Hz mono and passed to the note-detection model. Whatever the model reads as a note becomes one MIDI note in one track.
Practical limits for guitar: a chord is written as simultaneous notes rather than a guitar part; the file carries no string, fret, capo, tuning or tablature information; distortion, slides, bends and harmonics are not labelled; and any drum, vocal or backing bleed in the same file is merged into the same track. This tool does not separate instruments and does not produce sheet music.
Open the downloaded .mid in a MIDI editor and compare it with your recording before using it in a project. For the same converter on other inputs, see the MP3 measurements, WAV scale test, voice test and whole-song test.