Convert images, documents, video and audio in your browser. Your files stay on your device.
Keep just the sound: from the MP4 video you get a AAC file, with the bitrate and channels you prefer.
Drag one or more MP4 files onto the dashed area, or tap it to pick them from your device.
AAC is already selected: you can adjust bitrate, channels and volume.
Press “Convert to AAC”. When it’s done, download the files one by one or all together in a ZIP archive.
Good to know. For the best quality choose FLAC or WAV; for compatibility, MP3.
Source format
MPEG-4 Part 14
The most widespread video format in the world: phones, TVs, browsers and social networks all play it. It usually contains H.264 video and AAC audio, a pairing that gives good quality with compact files.
Target format
Advanced Audio Coding (ADTS stream)
The successor to MP3, used by YouTube, Apple Music and digital broadcasting. An .aac file contains the “bare” audio stream, with no container.
Audio and video use WebCodecs: they work in up-to-date Chrome, Edge, Opera and Samsung Internet, in Firefox 130+ and Safari 17+ (with a few limits on the formats they can create). If your browser can’t create the chosen format, we tell you before you start.
No. The conversion from MP4 to AAC happens entirely in your browser, using your device’s computing power. Files aren’t sent or stored anywhere: when you close the page they’re gone from memory too.
Up to 100 files at a time. There’s no fixed size limit: it depends on your device’s memory. On smartphones it’s best to work in smaller batches with heavy files such as videos.
Yes, with up-to-date Safari, Chrome, Firefox, Edge and Samsung Internet. On phones, converted files end up in the Downloads folder or the Files app.
Only to open the page (and, the first time, to download the components needed for that type of file). After that the conversion keeps working even if the connection drops.