Reduce AVI File Size Online
AVI files are often uncompressed or use older codecs that result in huge file sizes. Convert and compress your AVI to MP4 directly in your browser.
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AVI files and why they are large
AVI was designed in the early 90s and often stores raw or lightly compressed video. Converting to H.264 MP4 can reduce size by 85–95% with comparable quality.
How to Get Started
Key Features
AVI supported
Works with AVI files using common codecs like DivX, Xvid, and uncompressed video.
Massive size reduction
AVI files regularly shrink 85-95% when converted to H.264 MP4.
No upload
Your AVI stays on your device throughout processing.
Universal output
MP4 H.264 plays everywhere AVI cannot.
Frequently Asked Questions
Why are AVI files so large?
AVI predates modern video compression. Many AVI files use little or no compression, resulting in gigabytes of data for short clips.
What codecs in AVI are supported?
Most common AVI codecs (DivX, Xvid, uncompressed) are supported. Some exotic codecs may not decode in the browser environment.
Will the output play on my phone?
Yes. MP4 H.264 is universally supported on Android, iPhone, and all smart TVs.
My AVI is 4GB — can I compress it?
Very large AVI files may be limited by browser memory. Try a 2GB or smaller file if you encounter issues.
Related
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