Convert MP4 to AAC
Extract the audio from any MP4 video and save it as AAC. Free, no sign-up, and your file never leaves your device.
or drag & drop videos, audio or images here, or paste with Ctrl+V
MP4 · MOV · MKV · AVI · WebM · WMV · FLV · GIF · MP3 · WAV · M4A · and 40+ more
- Files never leave your device
- No sign-up, no watermark
- Free forever
How to convert MP4 to AAC
- Add your MP4 fileClick “Choose files” or drag & drop your MP4 file onto the page.
- Check the outputAAC is pre-selected. Optionally trim, crop, compress or tweak quality in the tabs.
- Convert & downloadClick “Convert & download”. Your AAC file is created on your device and saved instantly.
MP4 vs AAC
Short answer: AAC is a high-efficiency audio codec used by YouTube, iTunes and most streaming services.
What is MP4?
MP4 is the most widely supported video format. It plays on virtually every phone, browser, TV and editing app, and offers an excellent balance between quality and file size.
What is AAC?
AAC is a high-efficiency audio codec used by YouTube, iTunes and most streaming services.
Quality
Only the audio track is kept. If the codec already matches AAC (for example AAC inside MP4 → M4A) we copy it losslessly; otherwise we encode at a high-quality default bitrate you can change.
| MP4 | AAC | |
|---|---|---|
| Full name | MPEG-4 Part 14 | Advanced Audio Coding |
| Type | video | audio |
| Best for | Sharing, social media, websites and playback on any device | Streaming and mobile devices |
| MIME type | video/mp4 | audio/aac |
Last updated 2026-11-13
MP4 to AAC: FAQ
Is this MP4 to AAC converter free?
Yes. Converting MP4 to AAC is completely free with no watermark, no sign-up and no file limits beyond what your device can handle. Optional Pro features like 4K export and AI subtitles are available if you need them, and a single 4K export can be unlocked without a subscription.
Are my MP4 files uploaded to a server?
No, never. The conversion runs entirely in your web browser using FFmpeg compiled to WebAssembly. Your MP4 file never leaves your computer or phone, and we never store it, which makes it private and fast.
Will I lose quality converting MP4 to AAC?
Only the audio track is kept. If the codec already matches AAC (for example AAC inside MP4 → M4A) we copy it losslessly; otherwise we encode at a high-quality default bitrate you can change.
How do I convert MP4 to AAC on iPhone or Android?
Open this page in Safari or Chrome on your phone, tap “Choose files”, pick your MP4 file and tap “Convert & download”. No app install needed.
Can I convert multiple MP4 files to AAC at once?
Yes. Select several files and click “Convert all”. You can download them one by one or as a ZIP. Free users can batch-convert up to 5 files at a time; Pro removes the limit.
Can I edit the MP4 before converting?
Yes: trim, cut, crop, rotate, resize, change speed, adjust colour, add text, music or subtitles, and more, all before you export to AAC.