Convert AVI to AAC Online Free

Extract the audio from your AVI video and save it as AAC — the modern, efficient audio format that plays on every device. Great for modernizing audio from legacy AVI collections.

Quick Answer

ChangeThisFile extracts audio from your AVI video and encodes it as AAC using FFmpeg on our secure servers. AAC modernizes legacy AVI audio with better quality-per-bit and universal compatibility on iOS, Android, and streaming platforms. Files are auto-deleted, free with no signup needed.

Free, no signup Under 1 minute

Convert AVI to AAC

Drop your AVI file here to convert it instantly

Drag & drop your .avi file here, or click to browse

Convert to AAC instantly

AVI vs AAC: Format Comparison

Key differences between the two formats

FeatureAVIAAC
TypeMicrosoft video containerLossy audio bitstream (ADTS)
DeveloperMicrosoftMPEG / ISO standard
Audio codecMP3, PCM, or AC-3Advanced Audio Coding
File sizeModerate to large (video included)Small — efficient audio-only
Mobile compatibilityPoor — limited smartphone supportExcellent — native on iOS and Android
Quality vs sizeMP3 or PCM qualityBetter than MP3 at same bitrate
Use caseLegacy Windows desktop playbackMobile apps, streaming, automotive, modern devices

When to Convert

Common scenarios where this conversion is useful

Modernize legacy AVI audio for mobile device playback

AVI files are not supported natively on most modern smartphones. Extracting the audio as AAC gives you a compact, widely-compatible audio file that plays natively on iOS, Android, and every modern device.

Extract audio from old camcorder AVI recordings

Early digital camcorders recorded video as AVI files. Extract the audio as AAC to listen to old recordings on modern devices, share via messaging apps, or archive in a current format.

Convert DivX AVI movie audio for streaming apps

DivX AVI videos from the early 2000s often have MP3 audio tracks. Converting to AAC updates the audio to a more efficient modern codec accepted by streaming and podcast platforms.

Create audio files from AVI training videos

Corporate training videos from the 2000s-2010s are often AVI files. Extract narration or lecture audio as AAC to create audio-only versions for employees who want to listen while multitasking.

Prepare AVI audio for podcast editing

Some podcast content was recorded as AVI video files in older workflows. Extract the audio as AAC to import into modern podcast editors like Audacity, GarageBand, or Adobe Audition for cleanup and publishing.

How to Convert AVI to AAC

  1. 1

    Upload your AVI file

    Drag and drop your .avi file onto the converter or click to browse and select it. Files up to 500MB are supported.

  2. 2

    Server-side AAC encoding

    Your AVI is uploaded over HTTPS and FFmpeg extracts and decodes the audio track, encoding it as AAC. The video stream is discarded. Processing completes in seconds.

  3. 3

    Download your AAC file

    Click Download to save the .aac file. Both the original AVI and the converted AAC are automatically deleted from our servers after download.

Frequently Asked Questions

Most AVI files — especially DivX-era video rips — use MP3 audio. Home camcorder AVI files often use PCM (uncompressed) audio. Some AVI files from DVD rips use AC-3 (Dolby Digital). FFmpeg handles all of these when converting to AAC.

Yes. AAC is a more efficient codec than MP3. At equivalent bitrates, AAC delivers better audio quality, particularly at frequencies above 16 kHz. Converting AVI MP3 audio to AAC at a higher bitrate can improve perceived quality.

Yes. Converting between two lossy codecs (MP3 → AAC) involves re-encoding, adding a small additional quality reduction. At high bitrates (192+ kbps), this difference is typically imperceptible.

Yes. AAC is Apple's preferred audio format and plays natively on all iPhone, iPad, and Mac devices. AVI audio converted to AAC can be imported directly into the Music app or Files app on iOS.

FFmpeg uses a high variable bitrate setting by default, typically 192 kbps VBR AAC. This provides excellent quality for music, speech, and general content.

Yes. Android has supported AAC natively since version 1.0. AAC files play in the default media player and all major third-party apps on Android.

Yes. ChangeThisFile is completely free. No signup, no limits, no fees.

AAC produces better audio quality than MP3 at equivalent file sizes. For new audio files, AAC is generally the better choice. MP3 retains a compatibility advantage with very old devices that only support MP3.

Very fast — typically just a few seconds. FFmpeg only processes the audio stream; the video is discarded, making conversion much faster than full transcoding.

Yes. All uploads are HTTPS-encrypted and files are deleted from our servers after conversion. We never retain, access, or share your files.

Related Conversions

Ready to convert your file?

Convert AVI to AAC instantly — free, no signup required.

Start Converting