What is AAC (Advanced Audio Coding, raw ADTS stream)?
A .aac file is a raw AAC audio stream without a container, the codec behind M4A, YouTube and most streaming services.
Raw AAC usually comes from recorders or stream captures. For a music library, M4A holds the same codec with tags and accurate seeking.
File extensions: .aacMIME types: audio/aac
Advantages
- Efficient codec with good quality at low bitrates
- Widely supported by hardware decoders
- Simple stream, easy to cut
Disadvantages
- No tags or cover art in raw form
- Seeking is imprecise
- Lossy
Typical uses
- Radio and streaming captures
- Exports from recording apps
- Input for further processing
Compatibility
Plays in all major browsers and on most phones and players; music libraries usually prefer the M4A container.
Convert AAC to another format
Convert to AAC from another format
Frequently asked questions
Are my files uploaded to a server?
No. The conversion runs entirely in your browser with local code. Your files never leave your device, and there is no upload.
Is there a file size limit?
There is no limit on our side, but your browser memory is. Images work for very large files; for videos, files above a few hundred megabytes can fail on devices with little memory.
Will the quality suffer?
That depends on the target format and settings. Use the quality option to balance size and detail; lossless targets keep everything the source contained.
Which browsers are supported?
Current versions of Chrome, Edge, Firefox and Safari. Fast hardware paths are used where available, with a compatible fallback otherwise.