How to use the MP4 to FLAC converter
- Choose your MP4 video or drop it on the box.
- No quality setting needed: FLAC is lossless.
- Click "Convert to FLAC". A progress meter shows how far along it is.
- Download your FLAC and listen to it right on the page.
Why convert MP4 to FLAC?
FLAC stores the soundtrack of an MP4 without any further loss, which is useful for archiving a live performance or a concert video before editing it.
- MP4: usually lossy, so quality drops a little each time it is re-encoded.
- FLAC: lossless quality.
- FLAC: about half the size of WAV.
FLAC cannot add back detail that the MP4's AAC audio already lost, but it guarantees the conversion itself adds no new loss.
MP4 vs FLAC
| MP4 | FLAC | |
|---|---|---|
| Full name | MPEG-4 Part 14 | Free Lossless Audio Codec |
| Type | Video | Audio |
| Created by | Moving Picture Experts Group (MPEG) (2001) | Josh Coalson and the Xiph.Org Foundation (2001) |
| Compression | Lossy | Lossless |
| Typical codecs | H.264 + AAC | FLAC |
| Best for | Sharing videos online, phone recordings, social media uploads and streaming | CD rips, hi-res music and archiving |
| Plays on | Windows, macOS, iPhone, Android, smart TVs, game consoles and every modern browser | Android, Windows 10 and later, recent iPhones (Files app), VLC and hi-fi streamers; older iTunes and some car stereos do not |
Does converting MP4 to FLAC lose quality?
The soundtrack is decoded and stored as FLAC, which is lossless. Nothing more is lost in the conversion, but the FLAC cannot be better than the audio that was inside the video.
How long does it take?
Fast. Only the sound is decoded, so even a long video usually converts in well under a minute.
What is an MP4 file?
MP4 is a container that usually holds H.264 or H.265 video with AAC sound. It is built on Apple's QuickTime file structure and became an ISO standard in 2001. Because almost every phone, browser, TV and editing app can play it, MP4 is the safest choice when you need a video to just work.
What is a FLAC file?
FLAC compresses audio without throwing anything away: decode it and you get exactly the original. Files are about half the size of WAV. It is the favourite format for CD rips and hi-res music downloads.
Frequently asked questions
Is the MP4 to FLAC converter free?
Yes, completely free, with no sign-up and no watermark. Files up to 1 GB each can be converted, and there is no daily limit.
Do you keep a copy of my files?
We never receive them. All processing happens on your device, so there is nothing for us to store or delete.
Will the FLAC sound as good as the MP4?
The soundtrack is decoded and stored as FLAC, which is lossless. Nothing more is lost in the conversion, but the FLAC cannot be better than the audio that was inside the video.
Can I convert FLAC back to MP4?
Yes, use the MP4 Converter and choose MP4 as the output.
An MP4 plays without sound. What should I do?
The audio may use a codec your player does not support (for example AC3). Convert it to MP4 again so the sound becomes AAC.
Does it work on iPhone and Android?
Yes, in Safari, Chrome and other modern mobile browsers. Short files work best on phones; for long or high-resolution videos a computer is faster.