You may try isquint. It’s totally free, but I’m not sure if it could convert video to avi.
If you would convert video frequently on Mac, I recommend you an all-in-on mac video converter.
1. Convert various format video(MOV/MP4/FLV/AVI/WMV/MPEG...) to each other.
2. Support HD video.
3. Customize video specs.
4. Video editing function, including crop black bar on screen, trim time length for a specific video clip, merge several video clips into a single file etc.
5.Support batch conversion and merging video clips into one file.
I am afraid iSquint can not convert .MOV to AVI. You can try some free online converter.
But it can not convert big files.
You can also use this video converter for mac. It can convert .MOV to AVI on Mac with high quality.
Tanbee Video Converter for Mac
Video Converter for Mac is a powerful and easy-to-use mac video conversion software which helps you convert videos and audios between various formats for Mac easily and fast, such as AVI, MP4, MOV, MKV, WMV, MPEG, 3GP, VOB video and HD Video (MOD, TOD, MTS). Tanbee Video Converter for Mac makes most video files playable on the iPod, PSP, iPhone, Smartphones as well as many others. This Mac Video Converter can also extract audio from video, movie and convert audio to audio, like MP3, M4A, AAC, etc.
Tanbee AVCHD Covnerter for Mac
AVCHD Converter for mac is a full-featured tool for AVCHD camcorder users, which can convert AVCHD videos (MTS, M2TS, MOD, MOD) to common videos including AVI, MOV, MPEG, WMV, MP4, 3GP, FLV, SWF, and HD videos like HD AVI, HD MOV, HD MPEG, HD WMV. So you can share your masterpieces shot by Sony, Panasonic, JVC, Canon, Hitachi AVCHD camcorder on your favorite digital devices and more multimedia players.
Tanbee Flip Covnerter for Mac
Flip Converter for Mac, extremely intuitive Flip camera video converter. This Mac Flip Converter offers the most robust function to convert Flip videos to AVI, MOV, FLV, 3GP and other popular video formats on Mac OS X. It also natively supports converting AVI, MPG, WMV, DV, MOV, etc and more. With Tanbee Flip Converter for Mac, you can efficiently extract MP3, M4A, etc. audio from Flip video.
Tanbee iPad Video Covnerter Mac
iPad Video Converter Mac is designed for Apple iPad users to watch just about any video format on the iPad. Not only can this program convert general video (WMV, AVI, MPEG, FLV, 3GP) and audio formats to iPad friendly formats easily and rapidly, it can also convert HD videos including AVCHD (*.mts, *.m2ts), MOD, TOD to iPad HD video so you can enjoy movies on your wherever you go.
Tanbee Video Editor for Mac
Video Editor for Mac is specifically tailored for Mac users and video editing fans, which comes packed with video editing features: video trimming video, cropping video, splitting video, adjust special effects, join/merge several video files into one, set encoding parameters, etc.
You may download this mac video converter for a try, I know it can convert between avi and imovie(mov, mp4) video, my friends recommend it to me, it’s safe and works pretty well for me.
If you are interested in it, here is a step by step guide about how to use it
Hope it helps. Contact me if you have any other question or you can use