AVI to MP4 Converter
AVI is an old Windows video format that modern phones, browsers and social networks usually cannot play. Convert it to MP4 so it plays everywhere: on Windows, Android, iPhone, smart TVs, and when uploading to WhatsApp, Instagram or YouTube.
Free · No sign-up · Files stay on your device
How to use AVI to MP4
- 1Choose your AVI file.
- 2Click "Convert".
- 3Wait for the progress bar, then download the MP4.
Features
- H.264 video + AAC audio for maximum compatibility
- Keeps the original resolution
- Fast-start MP4 for instant web playback
- No file-size upload limits
- Files never leave your device
Why MP4?
MP4 with H.264 video and AAC audio is the most compatible video format in the world. Every modern device, browser and video platform supports it, which is why converting to MP4 is the easiest way to make a video play anywhere.
Private, in-browser processing
This tool uses FFmpeg, the open-source engine behind most professional video software, running inside your browser. The first time you use it, the engine (about 30 MB) is downloaded once and then cached, so later conversions start straight away.
Frequently asked questions
Are my files uploaded?
No. Processing happens on your device with FFmpeg compiled to WebAssembly, so your video and audio never leave your computer or phone.
Why does it take a while?
Video processing is demanding, and your browser does it on your own device instead of a big server. Short clips take seconds; long or 4K videos can take several minutes. Keep the tab open until it finishes.
Will the quality drop?
The video is re-encoded at high quality (CRF 23), which looks the same as the original to most viewers.