Free online MP3 to MID converter

A notation editor, sequencer, synthesizer, or older keyboard may require MIDI events instead of recorded audio. Converting the recording produces editable note data; renaming .mp3 to .mid does not perform the conversion.

What the MP3 format is

MP3 is a lossy, perceptually compressed audio format that stores a recording as encoded sound. Phones, music players, streaming and download services, digital audio workstations, browsers, and audio editors commonly use .mp3 files.

After decoding, an MP3 provides an audio waveform rather than separate note events. It normally contains no reliable note numbers, instrument parts, tempo map, or notation. Lossy compression, reverb, and mixing can remove or obscure details needed for transcription.

What the MID format is

MID is a common extension for a Standard MIDI File; .midi is another extension for the same general format. MIDI stores performance events such as note numbers, note-on and note-off timing, velocity, tempo, channels, controller changes, program changes, and track or sequence metadata. It stores no recorded sound.

MIDI data can be edited note by note, imported into notation software, used to control virtual instruments, or sent to an electronic keyboard. Files are usually far smaller than MP3 files, but playback depends on the destination synthesizer, sound bank, or virtual instrument. The result therefore will not reproduce the original vocal, ambience, distortion, or instrument tone.

Using the built-in converter

1. Open the MP3-to-MID converter on 101convert.com. The conversion can be performed in a browser without installing software.
2. Upload the .mp3 file and start the conversion.
3. Wait for the audio transcription to finish, then download the generated .mid file.
4. Open the file in a MIDI-compatible application such as MuseScore, GarageBand, Cubase, Ableton Live, or a hardware sequencer.
5. Inspect the piano roll or notation and correct missed notes, extra notes, timing, octave, tempo, and instrument assignments before using the result.

Use a local application instead when the recording is private, unreleased, or restricted from upload. Check the converter's current file-handling terms before submitting sensitive audio.

Using desktop transcription software

Desktop applications such as Melodyne, AnthemScore, WIDI Recognition System, and Spotify's open-source Basic Pitch can analyze audio and generate MIDI. Menu names vary by version, but the process is consistent:

1. Open or import the MP3 and allow the software to analyze its pitch and timing.
2. Choose a monophonic, polyphonic, or percussive detection mode when available. Monophonic mode suits one melody; polyphonic mode attempts chords; percussive detection is intended for rhythm rather than pitched notes.
3. Review the detected notes in the piano-roll or score editor. Remove false notes and correct pitch, duration, beat position, tempo, octave, and quantization.
4. Use File → Export → MIDI, File → Save As, or the application's equivalent MIDI command.
5. Save the result with a name such as song.mid, then verify it in the target sequencer or notation program.

Basic Pitch can run locally from a Python environment. A typical installation and command are pip install basic-pitch followed by basic-pitch output_directory input.mp3; use basic-pitch --help if the installed release has different options.

Quality and compatibility limits

This is transcription, not lossless format conversion. A clean recording of one vocal, flute, guitar, or piano melody is substantially easier to analyze than a mastered stereo mix containing vocals, chords, bass, drums, reverb, and effects. Full mixes can produce missed notes, false notes, wrong octaves, inaccurate durations, and overlapping parts that are difficult to separate.

When available, use an uncompressed WAV or lossless FLAC instead of an MP3, isolate one instrument or stem, reduce noise and reverb, and avoid heavily compressed or distorted sources. MP3 bitrate does not directly determine MIDI quality, but low-bitrate artifacts can increase pitch-detection errors. Sustained chords, drum parts, and polyphonic recordings commonly require manual editing even with specialized software.

Before importing the file, check its tempo, time signature, MIDI channels, program changes, pitch range, note timing, and key. MIDI has no universal sound: selecting a different synthesizer or sound bank can change the playback substantially. Copyright in the recording and underlying composition still applies to the generated transcription.