Convert AVI to MP3 Online
Extract audio from AVI video files and save it as MP3. Free, in your browser, no file uploads.
.avi · up to 100 MB
What you can do
AVI to MP3: recover audio from legacy video without the hassle
MP3, AC-3 and PCM
Correctly decodes the most common audio codecs found in DivX-era AVI files.
100% private
Your AVI files never leave your device. Local processing via WebAssembly.
Legacy archive
Recover soundtracks from DVD rips, camera recordings, and old DivX collections.
No installs
No VirtualDub, FFmpeg, or additional software needed. Works directly in the browser.
How it works
Three steps, no hassle
Upload your AVI file
Drag or select your .avi file. Up to 500 MB. No signup or installs required.
In-browser audio extraction
The audio stream from the AVI container is decoded and re-encoded to MP3 directly in your browser via WebAssembly.
Download your MP3
Audio ready for players, podcast platforms, or video projects. Compatible with any device.
FAQ
Got questions?
It depends on the original audio codec in the AVI. If the file contains native MP3 audio, extraction can be done without re-encoding (stream copy), preserving the exact quality of the original. If the original audio is uncompressed PCM, AC-3 (Dolby Digital), or another codec, re-encoding to MP3 is required, introducing one generation of loss. At an output bitrate of 192 kbps or higher, this loss is perceptually minimal for most musical material. For DivX-era files already containing 128 kbps MP3, the extracted audio faithfully preserves the original fidelity.
The AVI format (Audio Video Interleave), developed by Microsoft in November 1992 as part of Video for Windows, uses the WAVEFORMATEX codec identification system for audio. The most common audio codecs in AVI files are: uncompressed PCM (WAVE_FORMAT_PCM, the simplest), MP3 (WAVE_FORMAT_MPEGLAYER3, very common in DivX rips from the 2000s), AC-3 or Dolby Digital (WAVE_FORMAT_DOLBY_AC3, present in DVD rips), and less commonly AAC, OGG Vorbis (in non-standard AVI containers), and WMA. AVI files from 1999–2008 originating from DivX or Xvid DVD rips almost always use MP3 or AC-3. Older files from camera recordings or screen captures typically contain PCM.
Yes, significantly smaller. A 700 MB AVI of a typical 2000s feature film (with 128 kbps MP3 audio) will produce an MP3 of around 50–70 MB for 90 minutes of audio. If the AVI contains uncompressed PCM audio (approximately 10 MB per minute in stereo 44.1 kHz 16-bit), the reduction when exporting as 192 kbps MP3 will be about 5 to 6 times. In any case, the video stream (which occupies 90% or more of the AVI) is completely discarded during extraction.
Yes. AVI 2.0, also called OpenDML or AVI Index Extended, was developed by Matrox and other manufacturers in 1996 to overcome the 2 GB limitation of the original 32-bit RIFF-based AVI format. OpenDML files use the 'odml' index inside the container, enabling file sizes larger than 2 GB via an extended RIFF structure. Our extractor correctly handles both variants (AVI 1.0 and OpenDML 2.0) as well as AVI files with multiple audio tracks, extracting the first audio track by default.
Yes, that is one of the primary use cases. DivX and Xvid rips from the 1999–2010 period are AVI files with MPEG-4 Part 2 video (DivX, Xvid, MS-MPEG4) and MP3 or AC-3 audio. Extracting the audio lets you recover original soundtracks, sound effects, or dialogue from films without reprocessing the full video. The quality of these recordings varies but is representative of the state of the art in MP3 audio encoding of that era (typically 128 kbps CBR or VBR).
No. All processing happens in your browser via WebAssembly (FFmpeg compiled for the web environment). The AVI file never leaves your device or gets transmitted to any external server. This is especially relevant for personal archive files or old video recordings that may contain sensitive content.
Convert AVI to MP3: extract audio from legacy video with precision
The AVI (Audio Video Interleave) format was introduced by Microsoft in November 1992 as part of the Video for Windows package, with the goal of providing synchronized audio-video playback on personal computers of the era. AVI is a subtype of the RIFF (Resource Interchange File Format) container, the same binary format used by the WAV audio format. In its original design, AVI uses a 32-bit RIFF index that limits the maximum file size to 2 GB — a restriction overcome in 1996 by the OpenDML extension (AVI 2.0), developed by Matrox and other video capture hardware manufacturers. AVI's codec identification system is based on FOURCC identifiers for video and WAVEFORMATEX values for audio, inherited directly from the Windows multimedia API. The most common audio codecs in AVI are uncompressed PCM (the default in uncompressed recordings), MP3 via the WAVE_FORMAT_MPEGLAYER3 identifier, and AC-3 (Dolby Digital), particularly prevalent in DVD rips from the 2000s. The golden age of AVI as an internet video distribution format coincided with the rise of DivX (1999–2001), when groups popularized 'CD rips' of DVD movies as 700 MB AVI files optimized to fit on a CD-ROM.
Extracting audio from AVI to MP3 is technically a two-step process: first, demuxing the RIFF container to isolate the audio stream (stream 01 in AVI nomenclature, where stream 00 is always video), and second, transcoding the audio codec to the target MP3 format. When the AVI contains native MP3 audio, lossless extraction is possible via stream copy — copying MP3 frames directly from the AVI container to the destination MP3 file without re-decoding. This technique is preferred when the goal is to exactly preserve the original quality. When the audio is PCM (especially in camera recordings or screen captures), AC-3 from DVD rips, or any other non-MP3 codec, full decoding to PCM and re-encoding to MP3 with the LAME encoder is required. LAME (LAME Ain't an MP3 Encoder), the reference open-source MP3 encoder since 1998, implements high-quality VBR mode via Grill's psychoacoustic model 2 algorithm, producing files with the highest possible perceptual quality per bit. At 192 kbps, musical material from average-quality DivX rips is indistinguishable from the original for most listeners.
DivX-era AVI files represent one of the largest and least accessible digital heritage archives in personal multimedia history. Between 1999 and 2010, hundreds of millions of AVI files were created and distributed through forums, P2P networks such as eMule, Kazaa, and BitTorrent, and CD-ROM exchanges. Many of these recordings contain soundtracks, sound effects, and dialogue that exist only in these low-resolution video files — but with perfectly preserved audio. Extracting the audio as MP3 allows recovery of these audio recordings for archiving, remastering, or simple playback, without needing to play back the full video. Historical tools such as VirtualDub (developed by Avery Lee since 1998), Avisynth, and FFmpeg itself were the only alternatives for extracting audio from AVI until the arrival of web-based tools. Convertir.ai performs all AVI→MP3 extraction via FFmpeg compiled to WebAssembly in the browser, with no software installation required, no usage limits, and complete privacy — the video file never leaves the user's device.