MP4 to AVI Converter

AVI is still what many DVD players, older smart TVs, car screens, digital photo frames and Windows programs expect. This converter re-encodes MP4 (and MOV, MKV, WebM …) into an AVI they can play: Xvid-compatible MPEG-4 video with MP3 sound for DivX/Xvid-certified players, H.264 with MP3 for newer devices that read AVI, or Motion JPEG with uncompressed sound for editing programs. A DVD-player setting keeps the picture within 720 × 576 at 30 fps. It runs in your browser with the ffmpeg engine (about 30 MB, downloaded once); nothing is uploaded.

How to use this tool

1. Choose one or more videos.
2. Pick the AVI type: Xvid for players and TVs, H.264 for newer devices, Motion JPEG for editing.
3. Pick the quality, and the DVD-player size limit if the AVI is for a player.
4. Download the AVI files.

Formula

Xvid quality = fixed quantiser q 2 / 4 / 6 (lower = better); H.264 = CRF 19 / 23 / 27

Xvid files use the MPEG-4 Part 2 codec with the XVID FourCC, no B-frames (the most widely playable form) and MP3 at 192 kbps; surround sound is mixed to stereo. AVI cannot store a phone video's rotation flag, so portrait videos are turned upright, and non-square pixels are converted to square ones. Every video is re-encoded: AVI has no way to store the frame order that MP4's H.264 B-frames need.

Example

A 5-minute 720p phone video of 150 MB converted to Xvid, standard quality comes out at roughly the same size or larger, depending on how much the picture moves, because Xvid needs more data than H.264 for the same picture; "Small file" or the DVD-player limit makes it smaller. With the DVD-player limit, a 1920 × 1080 video becomes 720 × 404, which old players handle smoothly. As Motion JPEG, the same clip may be several times larger than the MP4.