How to use the MP4 to M4A converter
- Choose your MP4 video or drop it on the box.
- Pick an audio quality. 192 kbps is the usual choice; 320 kbps for music you care about, 128 kbps for speech.
- Click "Convert to M4A". A progress meter shows how far along it is.
- Download your M4A and listen to it right on the page.
Why convert MP4 to M4A?
M4A keeps the AAC audio that is already inside most MP4 files, so you get a small audio file that plays on iPhone, Mac and Android and imports straight into iTunes or Apple Music.
- MP4: usually lossy, so quality drops a little each time it is re-encoded.
- M4A: better quality than MP3 at the same size.
- M4A: native on Apple devices.
Because MP4 and M4A share the same container family, the result is clean and tags such as title and artist carry over.
MP4 vs M4A
| MP4 | M4A | |
|---|---|---|
| Full name | MPEG-4 Part 14 | MPEG-4 Audio |
| Type | Video | Audio |
| Created by | Moving Picture Experts Group (MPEG) (2001) | Moving Picture Experts Group (MPEG) and Apple (2001) |
| Compression | Lossy | Lossy |
| Typical codecs | H.264 + AAC | AAC (or ALAC) |
| Best for | Sharing videos online, phone recordings, social media uploads and streaming | iTunes music, voice memos and phone recordings |
| Plays on | Windows, macOS, iPhone, Android, smart TVs, game consoles and every modern browser | iPhone, Mac, Android, Windows 10 and later, and browsers |
Does converting MP4 to M4A lose quality?
Only the sound is kept and re-encoded as M4A. Video soundtracks are usually AAC at 128–256 kbps, so choosing 192 kbps or more keeps the M4A sounding the same as 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 an M4A file?
M4A is an audio-only MP4 file, usually holding AAC sound. It is the default for iTunes, Apple Music downloads, iPhone voice memos and many Android recorders. AAC sounds slightly better than MP3 at the same bitrate.
Frequently asked questions
Is the MP4 to M4A 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.
Is my file uploaded to a server?
No. The converter runs inside your browser using WebAssembly, so your file is processed on your own device and never sent to us or anyone else.
Will the M4A sound as good as the MP4?
Only the sound is kept and re-encoded as M4A. Video soundtracks are usually AAC at 128–256 kbps, so choosing 192 kbps or more keeps the M4A sounding the same as the video.
Can I convert M4A 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.