Audio to MIDI Converter

An Audio to MIDI converter analyzes an audio recording and extracts the musical notes (pitch, timing, and duration), then represents them as MIDI data. MIDI (Musical Instrument Digital Interface) is a standard protocol that records not the sound itself, but the performance data — which notes were played, when, and how hard. This allows you to edit the melody in any DAW (Digital Audio Workstation), change the instrument, adjust timing, or transcribe music for sheet music.

Monophonic audio (single notes at a time) works best — for example: vocal hums, whistling, solo flute, solo violin, or a single-instrument melody line. Polyphonic audio (multiple simultaneous notes, like chords or full band recordings) is significantly harder to transcribe accurately and may produce unreliable results. For best results, use clean recordings with minimal background noise, clear note attacks, and avoid heavy reverb or distortion.

Our tool uses autocorrelation-based pitch detection, which is quite accurate for clean monophonic signals within the range of approximately 50 Hz to 2000 Hz (roughly G1 to B6). The accuracy depends on audio quality, background noise, and the clarity of note transitions. The Sensitivity slider lets you fine-tune the detection threshold — lower sensitivity filters out spurious noises but may miss quiet notes; higher sensitivity catches more nuances but may introduce false positives. We recommend starting with the default setting and adjusting based on your results.

We support MP3, WAV, OGG, FLAC, M4A, and AAC formats. WAV files typically yield the best results since they are uncompressed and preserve the full audio fidelity. Compressed formats like MP3 and AAC are also supported, though heavy compression artifacts may slightly reduce pitch detection accuracy. Maximum file size is 50 MB. All processing happens locally in your browser — your audio is never uploaded to any server.

This tool is optimized for monophonic melody transcription. Converting polyphonic audio (multiple instruments playing simultaneously, chords, or full mixes) is an extremely complex problem even for professional software. For polyphonic conversion, we recommend dedicated desktop tools like Melodyne, AnthemScore, or built-in DAW features (Ableton Live's "Convert Harmony to MIDI", Logic Pro's Flex Pitch). Our tool excels at single-line melodies — vocal lines, instrumental solos, bass lines, and whistled tunes.

The downloaded .mid file can be imported into any DAW (Ableton Live, FL Studio, Logic Pro, Cubase, Reaper, GarageBand), notation software (MuseScore, Sibelius, Finale), or MIDI editor. Once imported, you can assign any virtual instrument to the MIDI track, edit individual notes, adjust timing and velocity, transpose the melody, or use it as a basis for sheet music. The MIDI file uses standard GM (General MIDI) format with 480 ticks per quarter note resolution.

The Minimum Note Duration setting (in milliseconds) filters out detected notes that are shorter than the specified threshold. This helps eliminate transient noises, accidental plucks, or brief pitch glitches that don't represent intentional musical notes. For fast, staccato passages, use a lower value (30–60 ms). For legato melodies or to clean up noisy recordings, use a higher value (100–200 ms). The default of 80 ms works well for most use cases.

All processing happens entirely in your browser. Your audio file is never uploaded to any server. We use the Web Audio API to decode and analyze the audio locally on your device. This means your data remains private and secure. The tool works even without an internet connection once the page has loaded. No account registration is required, and we do not store or collect any of your audio data.

Common reasons for detection issues include: (1) Audio contains polyphonic sections (multiple notes at once). (2) Heavy background noise or hum. (3) Notes outside the detectable frequency range (below ~50 Hz or above ~2000 Hz). (4) Very short or percussive notes that fall below the Min Note threshold. (5) Heavy reverb or delay blurring note boundaries. (6) Low-quality compressed audio with artifacts. Try adjusting the Sensitivity slider, reducing the Min Note duration, or re-recording with a cleaner signal path.

Monophonic detection assumes only one note sounds at any given time. It finds the single strongest frequency in each analysis window — this is relatively straightforward and accurate. Polyphonic detection must identify multiple simultaneous frequencies and assign them to different sources, which is mathematically far more complex (it's an underdetermined problem akin to solving a massive puzzle). Our tool focuses on monophonic detection to deliver reliable, fast results for the most common use case: melody transcription.