Convert old AVI videos to modern MP4, free, in your browser, no upload.
Open Video ConverterAVI is a legacy Microsoft container from the 1990s. It still shows up in old camcorder footage, screen recordings and downloads, but it is bulky and poorly supported on phones and the web. Converting AVI to MP4 with H.264 makes the file smaller and playable on every modern device and platform.
AVI usually holds an older codec that MP4 does not accept, so omnikitbolt re-encodes the video to H.264 at a high-quality setting. The result looks faithful to the source while being far more compatible and often smaller.
| Format | File Size | Quality | Compatibility | Use Case |
|---|---|---|---|---|
| MP4 | Small to Medium | High (H.264) | Universal | Sharing everywhere, web, social |
| AVI | Large | Variable (older codecs) | Legacy Windows | Old camcorder and archive video |
| MKV | Medium | High | Players, media servers | Multi-track archives |
| WebM | Small | High (VP9) | Modern browsers | Web embedding |
Open the AVI to MP4 converter
Click the button above or go directly to /tools/convert-video. No signup required- the tool is free and works instantly in your browser.
Drop your files
Drag and drop your AVI files onto the upload area, or click to browse. You can convert up to 20 files at once on the free plan (500 on Pro).
Download your MP4 files
Click Download on each file or use Download All as ZIP to save everything at once. All processing happens in your browser- nothing is uploaded to a server.
Complete privacy
Your files never leave your device. All conversion happens inside your browser using the Canvas API and WebAssembly.
Instant results
No upload, no queue, no waiting for a server. Conversion starts the moment you drop your files.
True batch processing
Convert up to 20 files at once on free (500 on Pro) and download them all as a ZIP. No signup required.
Always free
Core conversion tools are free forever. No watermarks, no file size caps on common formats, no account required.
Why convert AVI to MP4?
AVI is old and bulky and many phones, browsers and apps cannot play it. MP4 with H.264 plays everywhere and is usually a smaller file at the same quality.
Will the quality drop?
AVI codecs are not compatible with MP4, so a re-encode is needed. omnikitbolt uses a high-quality setting, so the result stays faithful to the source while gaining compatibility.
Is my AVI uploaded anywhere?
No. The conversion runs entirely in your browser with WebCodecs. The file never leaves your device.
Ready to convert? It takes less than 10 seconds.
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