Free online KAR to FLAC converter

What the KAR format is

KAR is a karaoke extension of Standard MIDI File. It stores note events, tempo, instrument assignments, timing data, and usually synchronized lyrics or karaoke text; it does not contain waveform audio.

Karaoke authoring tools and MIDI sequencers create KAR files, and karaoke players use them to play an instrumental arrangement while displaying lyrics. You may encounter KAR files in karaoke song libraries, MIDI archives, and music-composition software that imports MIDI-based arrangements.

What the FLAC format is

FLAC is a lossless audio format that stores decoded sound without discarding information through perceptual compression. It is suitable for archiving rendered performances, editing in audio software, and sharing files when smaller lossless audio is preferred over WAV.

FLAC can store the synthesized accompaniment produced from a KAR file, but it normally does not preserve the original MIDI notes, tempo controls, instrument changes as editable events, or separately displayed lyrics. Choose FLAC when the destination needs audio rather than a karaoke or MIDI performance file.

How to convert KAR to FLAC

Using MuseScore:

1. Install MuseScore and a suitable SoundFont if the installation does not include one.
2. Open the file with File → Open and select song.kar. MuseScore imports the MIDI tracks and may import lyric events as text, depending on the file.
3. Check the tempo, instruments, mixer levels, and playback. KAR files can contain missing instruments or nonstandard lyric events.
4. Select File → Export, choose FLAC as the format, select the output location, and export. If the installed MuseScore version does not offer FLAC, export WAV first and encode it with FFmpeg.

For command-line rendering, TiMidity++ can synthesize the KAR using its configured instrument patches:

timidity song.kar -Ow -o song.wav
ffmpeg -i song.wav -c:a flac -compression_level 5 song.flac

Another option is FluidSynth with a General MIDI SoundFont:

fluidsynth -ni soundfont.sf2 song.kar -F song.wav -r 44100
ffmpeg -i song.wav -c:a flac -compression_level 5 song.flac

Replace soundfont.sf2 with an installed SoundFont. The rendered character depends on that SoundFont, so two conversions can sound different even when they use the same KAR file.

If installing software is unsuitable, the built-in converter on 101convert.com can convert the file online for free without installation, subject to the service's supported input and output handling.

Quality, compatibility, and limitations

The conversion is not a direct lossless container change: MIDI performance data must be rendered into audio, and the selected synthesizer determines the instruments, dynamics, effects, and final sound.

Use a sample rate such as 44.1 kHz and render to WAV before encoding if the synthesizer has limited FLAC support. FLAC compression level changes encoding time and file size, not audio quality.

KAR lyrics are metadata or event data, not vocals. A converted FLAC will contain instrumental audio unless the original MIDI arrangement includes a vocal-like synthesized track or you record a vocalist while the KAR plays. Lyrics that need to remain searchable or synchronized should be retained by keeping the original KAR alongside the FLAC.