MP4 to AAC Converter
Processing entirely on your device — large files may take a moment.
MPEG-4 Video and AAC Audio exist for different jobs: MP4 (H.264) is the universal video format: every phone records it, every browser, TV, editor and chat app plays it. AAC is the sweet spot when you want modern compression in an open, non-Apple container.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How to convert MP4 to AAC
- 1
Select your files
Drag & drop your MP4 files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to AAC". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted AAC file individually, or grab everything at once as a ZIP archive.
Frequently asked questions
Is this MP4 to AAC converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Is there a file size limit for MP4 to AAC?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.