What FLAC gives you
FLAC (Free Lossless Audio Codec) compresses audio without throwing anything away. When you play a FLAC file, you get back exactly the samples that went in, like a WAV file, but the file is typically 40 to 60 percent smaller. It also supports rich tags and embedded cover art, which plain WAV handles poorly. That makes FLAC a favourite format for music collections and sound archives.
Is FLAC the right choice for MP4 audio?
It depends on what you plan to do. Most MP4 files carry AAC, a lossy codec. FLAC will preserve that decoded sound perfectly, but it will not make it better than the original. Converting MP4 to FLAC is a good idea when:
- you want to edit or remix the sound later and need a lossless working copy that is smaller than WAV;
- a music server, archive or DJ software in your setup expects FLAC for everything;
- the MP4 was made by professional software with high-bitrate audio and you want to keep every detail.
If you only want to listen on a phone, a lossless copy in M4A is smaller and keeps the original sound exactly.
Compression levels explained
FLAC offers levels from fast to maximum compression. All levels produce identical sound: the only differences are file size and how long saving takes. The default is a good balance. A higher level saves a few more percent of space, which adds up in a large collection.
Where FLAC plays
- Windows 10 and 11 Media Player, VLC, foobar2000 and most music players on Windows and Linux.
- Android phones and many car systems with USB.
- On iPhone, the Files app and VLC play FLAC. The Apple Music app does not import FLAC, so use M4A or AIFF there.
- Network players and media servers such as Plex, Kodi and Jellyfin.
The extraction runs locally in your browser, without uploads. For uncompressed audio for editors, see MP4 to WAV.