What happens when you convert MP4 to AAC
| Result | Only the soundtrack, encoded as AAC at 192 kbps by default |
|---|---|
| File size | About 1.4 MB per minute of audio |
| Speed | Fast: the video track is skipped, so only audio is processed |
| Opens in | phones, browsers and most players; some editors want it inside M4A |
Sizes are typical values; your files will vary with content and settings.
MP4 MPEG-4 Part 14
MP4 is the universal video container. With H.264 video and AAC audio it plays on every phone, browser, smart TV and social network, which makes it the safest choice for sharing.
MP4 converterAAC Advanced Audio Coding
AAC is the successor to MP3 and the audio codec inside most MP4 videos, YouTube and Apple Music. A raw .aac file is an ADTS stream without a container.
AAC converterHow to use the MP4 to AAC Converter
- 1
Choose a MP4 file or drop it onto the page.
- 2
Review the audio options. The defaults suit most files.
- 3
Click Convert and download your AAC when processing finishes.
Why convert MP4 to AAC?
MP4 is what phones, cameras, screen recorders and most video sites produce. Editing software sometimes prefers intra-frame formats like ProRes for heavy editing. Choose AAC when a player, hardware device or editor expects a raw AAC stream.
Audio extraction options
Only the audio track of the MP4 is processed, so this is much faster than a video conversion. Choose the bitrate or quality, optionally trim to a start and end time, and download the AAC.
Frequently asked questions
Will the AAC lose quality?
Both formats are lossy, so converting re-encodes the data once more. Using a high quality setting keeps the generational loss very small. Avoid converting the same file back and forth repeatedly.
How big will the AAC file be?
About 1.4 MB per minute of audio at the default 192 kbps, so a 10-minute MP4 gives roughly 14.4 MB. The size of the video track does not matter, because only the sound is kept. Choose 128 kbps for speech to make it about a third smaller.
Questions about privacy, file-size limits or conversion speed are answered in the general FAQ.