Convert MP4 files to AAC free in your browser — no signup, no install, and the file is never uploaded to a server.
Add your MP4 file
Drag the MP4 file onto the drop area above, or click it to pick a file from your device. You can add several files at once.
Confirm AAC as the output
AAC is already selected as the output format on this page. You can pick the bitrate — higher keeps more of the sound, lower makes a smaller file.
Run the conversion
Press the convert button. Video is re-encoded frame by frame on your own machine, so a long clip can take several minutes. The tab has to stay open.
Download the AAC file
When it finishes, download the AAC file. Converting multiple files gives you the option to download them together as a ZIP.
The most widely used video container, playable on virtually every device, platform, and browser. It typically carries H.264 video with AAC audio.
A lossy format designed as MP3's successor, delivering better quality at the same file size. It is the default for iTunes, YouTube, and streaming services.
Yes. MP4 to AAC conversion is completely free with no signup, no watermark, and no daily limit on the free plan for ordinary use.
No. The conversion runs entirely inside your browser using WebAssembly, so the MP4 file never leaves your device. That is also why it works without an internet connection once the page has loaded.
Yes — AAC is an audio format, so only the soundtrack is extracted. The video track is dropped, which is usually the point when you want just the audio.
The free plan handles files up to 200MB. Because processing happens on your own device, very large files depend on your computer's memory rather than a server quota.
Video converter
What each file format is, what it is used for, and which formats it can be converted to.
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