AVI to MP4 Converter
Modernize your AVI videos by converting to universally compatible MP4.
Video Converter
Convert videos between different formats (powered by WebCodecs)
Why Convert AVI to MP4?
AVI is an older Microsoft container format that produces large files and lacks support on many modern devices. Converting AVI to MP4 dramatically reduces file size, enables web and mobile playback, and ensures compatibility with virtually every player and platform.
Features
100% Private
Files never leave your device. All processing happens in your browser.
Instant Conversion
No waiting for server uploads. Convert AVI to MP4 in seconds.
Free & Unlimited
No signup, no limits, no watermarks. Convert as many files as you need.
Batch Support
Upload multiple files and convert them all at once with consistent settings.
Frequently Asked Questions
Why should I convert AVI to MP4?
AVI files are often very large and unsupported by modern browsers, smartphones, and streaming platforms. MP4 uses efficient H.264 compression, producing much smaller files with broad device support.
Will converting AVI to MP4 reduce quality?
There may be minimal quality loss from re-encoding, but MP4 H.264 is highly efficient. At high bitrate settings the difference is virtually imperceptible while file sizes drop significantly.
How much smaller will my MP4 file be?
Depending on the original AVI codec, you can expect 50-80% file size reduction. An uncompressed 1GB AVI might become 100-200MB as an MP4.
Is the AVI to MP4 conversion done in my browser?
Yes. The conversion uses WebAssembly-based processing entirely in your browser. Your video files are never uploaded to any server, keeping your data private.
Can I convert AVI files with subtitles or multiple audio tracks?
The converter handles the primary video and audio streams. Embedded subtitles and additional audio tracks may not transfer. For complex files, consider a desktop tool.
How It Works
This converter uses your browser's built-in WebAssembly to process files locally. Your AVI files are decoded and re-encoded as MP4 entirely on your device. Nothing is uploaded to any server.
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