AVI to MP3 Save the audio from old AVI files
Most AVI files that people still have are old: camcorder transfers, capture card recordings, files downloaded years ago, discs that got copied to a hard drive and then to the next hard drive. This page pulls the audio track out of those files and hands you an MP3, so the part worth keeping stops depending on a player that still understands the old video codecs. It runs in this tab, so the file is never uploaded.
- 128 kbps MP3
- Nothing uploaded
- Up to 20 files
Convert AVI to MP3
MP4, MOV, M4V, MKV, AVI, WMV, WebM, TS, MTS and more
Up to 20 clips at once
Privacy-first. No uploads. If this helps, share it.
- The archive stays where it is
Nothing is sent for processing. The page opens the AVI from your disk, reads the audio track with FFmpeg compiled to WebAssembly and writes the MP3 back to your downloads. Old family recordings often exist in one copy on one drive, and that copy never has to travel.
- It reads the old stuff
The bundled build demuxes AVI directly and decodes the audio tracks these files actually carry: MP3 from the DivX era, uncompressed PCM from capture cards, and the ADPCM variants old camcorder software wrote.
- 20 files per batch, 1 GB each
Point it at a folder of old clips instead of feeding it one file at a time. The queue works through them in order, and each finished MP3 appears on its own card as soon as it is ready.
How to convert AVI to MP3
Add the AVI, leave the target on MP3, and the audio track is decoded and written out as a 128 kbps, 44.1 kHz MP3 in your browser. The video stream is skipped rather than converted, so this is one of the quicker jobs on the site even with a large file. Nothing is sent anywhere, and your original AVI is left exactly as it was.
- Add your AVI files
- Leave the target on MP3
- Download the audio
AVI and MP3, side by side
An AVI is a box from 1992 holding a video stream and an audio stream. An MP3 is the sound on its own, a run of audio frames with no separate tracks inside it. Here is what actually differs between the file you have and the file you get.
| What changes | AVI source | MP3 output |
|---|---|---|
| Container | AVI, the RIFF based format Microsoft shipped with Video for Windows in 1992 | MP3, audio frames with no container wrapped around them |
| Video stream | Usually DivX or XviD, sometimes MJPEG from a capture card or an older codec such as Cinepak | Dropped. It is never decoded, which is why the job finishes quickly |
| Audio stream | Frequently MP3 already, otherwise uncompressed PCM or an ADPCM variant | MP3 at 128 kbps and 44.1 kHz, re-encoded in every case |
| Where it opens | Wants a player that still ships the old decoders, in practice VLC | Phones, car stereos, podcast apps, editors, and very broad hardware and software support |
| Size | Whatever the video costs, plus audio that runs about 1411 kbps when it is uncompressed CD rate stereo | Roughly 1 MB per minute, set only by the length of the recording |
The extension tells you nothing about what is inside. Two files both called .avi can hold completely different codecs. If you want to know before converting, VLC lists both streams under codec information.
Sometimes it is about size, sometimes about portability
When the AVI holds uncompressed PCM, which is common with capture cards and older camcorder software, the saving is large: a track running around 1411 kbps becomes one running at 128. When the AVI already holds MP3, which the DivX plus MP3 combination made very common, the point is not size but portability. You end up with a file that plays anywhere instead of a track sitting inside a container most modern apps stopped caring about.
Be clear about the tradeoff: this is always a re-encode, never a copy of the existing track. A source already sitting at 192 kbps steps down to 128, and a source below 128 gains nothing from being encoded at 128. The sound comes across as it is, in a more portable file.
What the MP3 gets you, and what it leaves behind
MP3 is the safest audio format there is. A car head unit reading a USB stick, a twelve year old media player, a phone, a podcast app, an editor, a transcription service: all of them take MP3 without a conversation. That is the whole reason to lift the audio out of a container that needs a legacy decoder to open at all. What the MP3 cannot do is carry the rest of the file with it.
The picture does not come along. If you want the video too, that is a separate conversion of the same file.
Nothing else travels either: no subtitle track, no chapters and no second audio track for a commentary or a dub. Old AVIs rarely carry artist or title tags to begin with, so expect an untitled MP3 and name it yourself when you save it.
There is no way back. An MP3 cannot become an AVI again, so keep the original wherever it already lives.
Get the audio out in three steps
Nothing leaves your device at any point.
Add the files
Drop in one AVI or a whole folder of them, up to 20 at a time and 1 GB each. That covers full length camcorder transfers and old disc rips without splitting anything first.
Let it read the audio track
The audio stream is decoded and written out at 128 kbps, 44.1 kHz. Because the video is skipped rather than converted, this runs far quicker than turning the same file into an MP4.
Save the MP3
Take the files one at a time or grab the batch as a zip. Your original AVI files are untouched on disk.
Why people pull audio out of AVI files
Almost nobody converts a brand new AVI. The reasons are close to identical every time, and they are all about age.
The sound is the part that ages well
A DivX transfer of a 1999 camcorder tape looks its age on any modern screen. The voices on it do not. When what you actually want to keep is someone talking, the audio is worth separating out and storing on its own.
No codec pack required
Old AVIs are the classic case of a file that plays on the one machine that has the right decoders installed and nowhere else. An MP3 has no such requirement, so the recording survives the next computer, and the one after that.
Uncompressed captures are enormous for no reason
Capture software often wrote raw PCM audio because it was cheap at the time. Stored at 128 kbps instead, the same recording takes a small fraction of the space, which matters when you are moving a shelf of old files onto one drive.
A folder at a time, not a file at a time
Archive work arrives in bulk. Twenty files per batch, and since only the audio is decoded, a queue of old clips gets through much faster than a video conversion of the same queue would.
Old home video is not the sort of file you hand to a stranger
The AVIs still sitting on people's drives are birthdays, weddings, a grandparent talking, a school play, a band practice in someone's garage. Quite often the tape is long gone and the file is the only copy left. Uploading that to an unknown converter to save a step is a bad trade, and there is no way to un-upload it afterwards.
This page has no upload step to opt out of. The decoding happens in the tab you are reading, so there is no server copy to delete, no processing history and no account to attach one to.
What that means in practice
- The file never leaves your device
- We never see the video or its file name
- No account, no watermark, no sign in wall
- The work runs on your machine, so a very long recording still needs a few minutes
AVI to MP3 troubleshooting
Related conversions
Need a different format? These open the same private browser converter, preconfigured for another conversion.
- MKV to MP4
Rebuild an MKV as an MP4 so Safari, iPhones, TVs and editors will open it. Usually a lossless remux.
Open this converter - AVI to MP4
Turn old DivX and XviD AVI files into MP4 that phones will actually play. Runs in your browser.
Open this converter - WMV to MP4
Turn old Windows Media files into MP4 that modern devices will actually open.
Open this converter
More free tools
Convert Video
Convert almost any video to MP4 or MP3 in your browser. Nothing is uploaded.
Open toolCompress Video
Shrink a video to fit Discord, WhatsApp or email size limits. Private, in your browser.
Open toolRemove Audio from Video
Strip every audio track from a video. Free, in your browser, no upload.
Open toolFrequently asked questions
Add the file at the top of this page, leave the target on MP3 and download the result. The audio is decoded in your browser and written out at 128 kbps, with no upload and no account.
Last reviewed in August 2026 for browser based AVI audio extraction.