MP4 to M4A Converter
or drop your images here
How to Convert MP4 to M4A Online
MP4 to M4A: what changes in the file
This tool takes a MP4 file, processes it with FFmpeg on DownloadVideo.vn servers and returns a M4A file.
The picture track of the MP4 is dropped; only the audio is kept and packaged as M4A.
Both MP4 and M4A are lossy, so converting adds another generation of compression: a small further loss that is usually hard to notice after one conversion.
How MP4 and M4A differ
| Property | MP4 | M4A |
|---|---|---|
| Full name | MPEG-4 Part 14 | MPEG-4 Audio (AAC in an MP4 container) |
| Introduced | ISO/IEC MPEG, 2003 | Apple / MPEG, 2003 |
| Compression | lossy | lossy |
| Common codecs | H.264, H.265/HEVC, AV1, AAC | — |
| Strengths | plays on virtually every phone, browser, TV and editor; standard upload format for YouTube, TikTok, Facebook, Instagram | standard for iTunes, iPhone ringtones and voice memos; keeps tags and cover art |
| Limitations | lossy codecs: every re-encode loses a little quality | some older car stereos and Windows apps do not recognise the extension |
Measured with a sample file
On September 25, 2026 we ran the tool on our production server with a sample file: a 10-second 1280×720 video (H.264 + AAC), 3.9 MB.
Result: 3.9 MB → 159 KB, processed in 1.9 s. Output: AAC audio at 44.1 kHz stereo, 128 kbps.
Real sizes depend on your content (how complex the picture and sound are, and the length); the figures only show the order of change.
Before you convert
- The tool always re-encodes the picture and sound, even when the source codec would already fit the target format.
- Up to 500 MB per file; a conversion that runs longer than 10 minutes is cancelled.
- The file is sent to our server for conversion and deleted as soon as processing ends, including when it fails.
Frequently asked questions
Is the picture from the MP4 kept in the M4A?
No. M4A is an audio format, so only the sound is kept.
Does converting MP4 to M4A reduce quality?
Slightly: it is a second round of lossy compression. One conversion is usually hard to notice, but repeated conversions add up.
How does the file size change from MP4 to M4A?
With our sample file: 3.9 MB → 159 KB. Your file may differ depending on its content.
