Add your AVI file
Drop one or more .avi files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Pulling the soundtrack out of a .avi video into .aac audio keeps what you can hear and drops the picture entirely. Free, private, and validated — the file never leaves your browser.
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.Pulling the soundtrack out of a .avi video into .aac audio keeps what you can hear and drops the picture entirely. An .avi file is Microsoft's Audio Video Interleave container, one of the oldest video wrappers still in circulation. It stores video and audio in alternating chunks inside a RIFF structure, and the extension remains common on older camcorder captures and DivX-era rips.
An .aac file holds raw Advanced Audio Coding data, usually as an ADTS stream. AAC was designed as MP3's successor and delivers audibly better quality at the same bitrate, though the bare .aac extension is rarer than AAC audio traveling inside .m4a or .mp4 files. For this route the practical draw is noticeably more efficient than MP3 at equal bitrates and hardware decoding in essentially every phone and TV — balanced against raw ADTS files handle tags and cover art poorly, which is worth knowing before you commit a large batch.
The usual reason to take .aac audio out of a .avi file is that only the sound matters — a talk, interview, song, or podcast segment. Keeping the video stream would waste storage, and a dedicated audio file is easier to trim, tag, and play. On the source side, no streaming support of any kind; on the target side, the payoff is noticeably more efficient than MP3 at equal bitrates, which is exactly what you want for receiving the audio track copied out of MP4 video without re-encoding.
| Aspect | AVI video (.avi) | AAC audio (.aac) |
|---|---|---|
| Format type | Container — quality depends on the codecs and settings inside | Lossy — discards detail it judges invisible to shrink files |
| How it stores data | interleaves audio and video chunks inside a RIFF file, with the codec identified by a four-character FourCC code | a pure MDCT transform codec, free of the hybrid filterbank compromise that limited MP3 |
| Strongest at | playing back footage digitized from DV and Hi8 tapes | receiving the audio track copied out of MP4 video without re-encoding |
| Weak spot | no streaming support of any kind | raw ADTS files handle tags and cover art poorly |
| Metadata | rIFF INFO chunks store basic fields such as title, artist, and encoding software, but nothing comparable to ID3 or MP4 atoms exists | no standard tag container exists for raw ADTS streams; ID3 tags are sometimes prepended but poorly supported, so wrapping in .m4a is the reliable way to tag AAC |
Drop one or more .avi files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
Select .aac in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if AAC is selectable, the route is real and validated.
Press Convert. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded.
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid AAC file. Outputs keep the original filename with the .aac extension.
Since avi is container-oriented and aac is lossy-oriented, the conversion preserves the source content exactly as stored; no additional compression pass is applied beyond what .aac itself requires.
Yes — the .avi file is processed inside your browser tab and never uploaded. A WebAssembly FFmpeg build demuxes the audio track and re-encodes it locally; the video stream is simply discarded. Close the tab and the file is gone from memory.
AAC decoding is built into every browser, phone, and operating system, whether the audio arrives as a raw .aac stream or inside an .m4a wrapper. The last holdouts are elderly MP3-only car stereos and bargain portable players.
Much smaller — the video stream is usually 80–95% of a .avi file's weight, and it is discarded entirely. The remaining audio is re-encoded at the bitrate implied by your quality setting.
This converter strips container metadata deliberately (the FFmpeg command runs with metadata mapping disabled) so exported files do not leak recording details. In the source, rIFF INFO chunks store basic fields such as title, artist, and encoding software, but nothing comparable to ID3 or MP4 atoms exists; none of it is transmitted anywhere because the file never leaves your browser.