Browser edition: files stay on your device. Up to 100 MB total and 10 minutes. First use downloads a 32 MB engine. Some formats depend on codec support. Public-link downloading is not ready on this free deployment.
Convert MP4 to FLAC
Convert MP4 to FLAC online for free. Extract the audio track at the bitrate you choose.
How to convert MP4 to FLAC
- Add your fileDrop it on the page, choose it from your device, or paste it with Ctrl+V.
- ConvertAdjust settings if you like, then press the button. You'll see live progress.
- Browser processing uses original files on your device. Public-link downloading is unavailable.
What happens to your file
MP4 files are common for sharing, uploading to social networks, playing on any device, but not every app or device opens them. FLAC is ideal for archiving CDs, hi-fi listening, music collections. Spool converts MP4 to FLAC with FFmpeg — real decoding and encoding, not a renamed file extension.
Audio only. Spool drops the video stream and keeps the soundtrack. The audio is encoded to FLAC losslessly from the decoded source. Tags such as title and artist are carried over when present.
Settings
- Sample rate — Original, 48 kHz, 44.1 kHz, 22 kHz
- Channels — Original, Mono
MP4 vs FLAC
| MP4 | FLAC | |
|---|---|---|
| Full name | MPEG-4 Part 14 | Free Lossless Audio Codec |
| Created by | ISO / MPEG, 2001 | Xiph.Org Foundation, 2001 |
| Type | Video container | Lossless audio |
| Typical contents | H.264 or H.265 video with AAC audio | FLAC (lossless) |
| Best for | sharing, uploading to social networks, playing on any device | archiving CDs, hi-fi listening, music collections |
| Strength | Plays everywhere, including iPhone, Android, Windows and macOS | Bit-perfect, lossless quality |
| Weakness | Lossy: every re-encode loses a little quality | Several times larger than MP3 |
About MP4
- Type
- MPEG-4 Part 14
- Contains
- H.264 or H.265 video with AAC audio
- Use
- sharing, uploading to social networks, playing on any device
About FLAC
- Type
- Free Lossless Audio Codec
- Contains
- FLAC (lossless)
- Use
- archiving CDs, hi-fi listening, music collections
FAQ
What bitrate should I choose for FLAC?
FLAC is lossless, so there is no bitrate to choose — you can only change the sample rate or switch to mono.
Can I convert several MP4 files at once?
Yes. Drop up to 10 files at a time — each one is converted in parallel and you can download them individually or all at once.
Is there a file size limit?
Convert and edit files on your device. The browser edition accepts up to 100 MB total, media up to 10 minutes and video up to 4K. Codec availability and device memory can limit individual jobs.
Is this MP4 to FLAC converter free and safe?
Yes. There are no pop-ups, redirects or fake download buttons, and no software to install. Files are transferred over HTTPS, processed in isolated job folders and deleted automatically.