AVI to MP4 Converter
Convert AVI video files to MP4 format online. Free, fast, and private.
Upload your AVI files and convert them to modern MP4 format. AVI is a legacy video format from Microsoft that produces very large files and is not supported by most modern devices, browsers, or social media platforms. MP4 gives you smaller files with better quality that play everywhere. All conversion happens in your browser using WebAssembly. Your videos never leave your device. Need to convert other formats? Try MKV to MP4 or our video compressor.
Drop AVI files here
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Supports: AVI video files
How It Works
- 1Upload AVI files
Click or drag and drop your .avi video files. AVI files are typically from older cameras, Windows software, or legacy recordings.
- 2Choose quality settings
Select output quality and resolution. Converting AVI to MP4 often reduces file size significantly while maintaining quality.
- 3Convert and download
Click Convert to MP4 and download your files. Preview the converted video before saving. Need to trim it? Use the Video Trimmer.
Frequently Asked Questions
Why convert AVI to MP4?
AVI is a legacy video format from the 1990s created by Microsoft. AVI files are typically very large because they often use minimal or no compression. Most modern devices, smartphones, smart TVs, and web browsers cannot play AVI files. Converting to MP4 gives you much smaller files that play everywhere.
Will the file size get smaller?
Yes, significantly. AVI files are often uncompressed or minimally compressed, resulting in very large file sizes. Converting to MP4 with H.264 encoding typically reduces file size by 50-80% while maintaining good visual quality. See our AVI vs MP4 comparison.
Where do AVI files come from?
AVI files are commonly from older digital cameras, camcorders, screen recording software, Windows Movie Maker, and legacy video editing tools. If you have old video archives in AVI format, converting to MP4 makes them easier to store, share, and play on modern devices.
Are my videos uploaded to a server?
No. All conversion runs in your browser using FFmpeg WebAssembly. Your videos never leave your device. No data is uploaded, stored, or tracked. See our security page.
Will the video quality change?
With High quality setting, the conversion preserves excellent visual quality. Since AVI files often use older codecs, the modern H.264 encoding in MP4 can actually look just as good or better at a fraction of the file size. You lose nothing meaningful.
Is this converter free?
Yes. This AVI to MP4 converter is completely free with no file limits, no signup, and no watermarks. Convert as many videos as you need. You can also compress your MP4 videos or extract audio from your videos.