SUONO TOOLS AUDIO WORKBENCH · TOKYO PWR
U-09

AVI → MP4
READOUT
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Manual

  1. Why convert AVI to MP4

    AVI is an older container format still used by some digital cameras, capture devices, and legacy recording hardware. Smartphones, modern video editors, and most social platforms either don't support AVI or can't play certain codec combinations inside it. Converting to MP4 (H.264) makes the file work with nearly every current device and app.

  2. How to use it

    (1) The output format is already set to MP4 on this page. Drag and drop your AVI file onto the drop zone, or click it to choose one — once loaded, its resolution, length and codecs are shown. (2) Optionally set a resolution (original / 1080p / 720p / 480p) and quality (high / standard / light). (3) Press convert; a progress bar tracks the encode, and a download button plus a before/after size comparison appear once it finishes.

  3. What happens to the video and audio

    AVI files are often built with older codecs (DivX, Xvid, or even uncompressed video), which tends to mean large file sizes and limited playback support. Converting to MP4 always re-encodes to H.264 video with AAC audio (falling back to Opus if AAC isn't available), keeping the file size down while making it playable on current devices and apps. This uses the browser's built-in WebCodecs API to encode with your device's hardware (GPU), so it's relatively fast.

  4. FAQ

    I want to play an old camcorder AVI file on my phone.
    Converting to MP4 makes it playable in most phones' default video player. Keep the resolution at 'original' — it works fine.
    Why are AVI files often so large?
    Older devices frequently export AVI with uncompressed or inefficient codecs, so it's often much larger than an MP4 (H.264) at the same visual quality. Converting can shrink the file significantly.
    My video editor won't import the AVI directly.
    Some modern editors don't support the older codecs sometimes found inside AVI files. Converting to MP4 (H.264) gives you a file most editors can drop straight onto a timeline.
    Is my file uploaded anywhere?
    No — the video is processed entirely inside your browser and never sent to a server.