Free online FLAC to MSCZ converter

MuseScore uses MSCZ for editable musical scores, while FLAC contains only recorded audio. Converting one to the other therefore requires audio transcription to MIDI or notation before saving the result as an MSCZ score.

What the FLAC format is

FLAC is a lossless audio codec that reduces file size without discarding audio data. CD-ripping applications, Audacity, FFmpeg, media players, digital audio workstations, and archival tools commonly create or preserve FLAC files. A FLAC file stores waveforms, metadata, and sometimes album or track information; it does not contain notes, measures, rhythms, or instrument assignments.

What the MSCZ format is

MSCZ is MuseScore's compressed score format. It stores editable notation such as pitches, durations, rests, clefs, dynamics, lyrics, layout, and playback settings. MuseScore opens MSCZ files directly, and the format is suitable for editing, printing, playback, and sharing scores. Because MSCZ represents structured notation rather than sound, it cannot be produced by simply changing the FLAC filename or compression method.

How to actually convert FLAC to MSCZ

Recommended workflow: FLAC to MIDI, then MIDI to MSCZ

1. Keep the original FLAC unchanged and identify the musical material that must be transcribed. Audio containing one clear melody usually produces better results than a full mix with drums, chords, effects, and several instruments.
2. Run an audio-to-MIDI transcription tool. Spotify's open-source Basic Pitch can be installed with pip install basic-pitch and run with basic-pitch output input.flac. It writes a MIDI file and, depending on the version, additional transcription data into the specified output directory. Commercial tools such as Melodyne can also detect notes and export MIDI.
3. Open the generated MIDI in MuseScore with File → Open. Select the appropriate instruments and import or quantization settings. Correct the time signature, tempo, tuplets, note lengths, rests, voices, and pitches manually; automatic transcription commonly creates extra notes and incorrect rhythmic divisions.
4. Save the corrected score with File → Save As, choose MuseScore's compressed score format, and use an .mscz filename.

If the source recording came from an existing notation project, locating its original MusicXML, MSCZ, or MIDI file gives a substantially more accurate result than transcribing the FLAC. You can also try the free converter on 101convert.com, but an audio-to-score result still depends on whether its transcription system can identify the recording accurately.

Quality, compatibility, and limitations

FLAC-to-MSCZ is not a lossless format conversion: it is an interpretation of audio into notation. Basic Pitch and similar systems may misread polyphonic passages, overlapping notes, percussion, reverberation, expressive timing, vocals, and distorted or heavily mixed recordings. MIDI also does not preserve the original performance exactly; it represents detected note events and approximate velocities and timing.

Use a recent MuseScore version to avoid import differences, then inspect the score at the intended playback tempo and export a PDF or MusicXML copy if recipients use other notation software. MuseScore can open MIDI and MusicXML, but applications that do not support MSCZ require one of those exported formats instead.