Is AVI to MP4 free? Is there a watermark?

Yes — AVI to MP4 is free to use with no sign-up or watermark. Very large files can still be limited by your browser's available memory and processing resources.

Do my files get uploaded to a server?

No. AVI to MP4 runs entirely in your browser with WebAssembly, so your AVI file never leaves your device and nothing is stored or seen by us.

What can I put in, and what do I get out?

AVI to MP4 accepts AVI and gives you back a MP4 file. Actual codec support depends on what the bundled engine or browser decoder can read.

Will I lose quality converting to MP4?

The H.264 conversion is lossy rather than a reversible container change. Keep the source and compare motion, fine text, colour, and audio sync in the result.

Free tools · Convert

AVI to MP4

Convert a legacy AVI video into H.264/yuv420p MP4 with AAC audio for broader playback compatibility. Actual codec support varies. No upload or watermark.

Runs entirely in your browser. Your file is never uploaded — no watermark, no account.

Drop a file or click to chooseAVI

Get a better result

Best for: Legacy camera exports, archive clips, and older downloaded AVI files that need a current H.264 playback container.
Input → output: AVI picture and sound are decoded into H.264/yuv420p MP4 video with 128 kbps AAC audio. The operation transcodes both streams.
Quality tip: Older AVI codecs vary widely, so process a brief sample and verify aspect ratio, interlacing, frame order, colour, and sound first.
Know before running: The conversion is lossy and cannot repair damaged frames, truncated indexes, or missing audio. Obscure legacy codecs may be absent from the browser engine entirely.
Next step: Resize video when the modernized file also needs a standard delivery height.

How to use AVI to MP4

1
Choose your file. Drop a supported AVI file into the tool, or click to select one. It stays on your device — nothing is uploaded.
2
Run locally. Press Run to begin. The first processing run loads the browser engine before local processing begins.
3
Download. Review the result, then download the finished file from your browser with no watermark.

Frequently asked questions

Is AVI to MP4 free? Is there a watermark?: Yes — AVI to MP4 is free to use with no sign-up or watermark. Very large files can still be limited by your browser's available memory and processing resources.
Do my files get uploaded to a server?: No. AVI to MP4 runs entirely in your browser with WebAssembly, so your AVI file never leaves your device and nothing is stored or seen by us.
What can I put in, and what do I get out?: AVI to MP4 accepts AVI and gives you back a MP4 file. Actual codec support depends on what the bundled engine or browser decoder can read.
Will I lose quality converting to MP4?: The H.264 conversion is lossy rather than a reversible container change. Keep the source and compare motion, fine text, colour, and audio sync in the result.