Why we convert MP4 to AVI? As known to all, MP4 is the most popular format that is commonly used in video sites, mobile phones, portable players and many other devices. Though this format is the most widely used one, some of the mainstream media players and video editing software, for example Windows Media Player does not support the MP4 format and require MP4 to AVI conversion. If you have collected lots of MP4 videos, and you would like to enjoy them on some AVI-compatible players, you'd better take 3rd-party application to convert MP4 to AVI. Below listed are three best ways for you to do the MP4 to AVI conversion simply and easily.   Method 1: Convert MP4 to AVI on Mac/Win with Apowersoft Free Online Video Converter Apowersoft Free Online Video Converter is a free and fast online video converter to convert your video or audio files on your PC hard drive or portable devices. This program is available to all Mac and Windows users and requires no downloading and installation. You don't need to pay for its web-based services and you can convert MP4 to AVI for Mac or Win easily as you like. Besides converting MP4 to AVI, it also supports converting videos to MP4, AVI, MOV, WMV, WEBM, ASF, MKV, MPG, 3GP, DV, SWF, FLV, VOB (video formats) and MP3, WAV, WMA, AAC, FLAC, OGG, RA (audio formats).In case you are eager to convert video online with no costs and restriction, this app may come to your first choice. The process was so simple and conveniently quick, and you can finish the whole MP4 to AVI conversion with three steps.   1. Click Browse button and upload the original MP4 video you want to convert in the app. 2. Choose AVI formats and do video settings (Resolution, Bitrate, Frame Rate) if needed. 3. Click Convert button to start the specific MP4 to AVI conversion.   However the video or audio formats this free online service supported are limited and it may take a little longer to convert larger videos, and the video or audio parameter settings are not sufficient enough. It does not come with video editing features so that users can not do unique video customization.   Method 2: Convert MP4 to AVI on Win/ Mac with Handbrake Handbrake is another versatile, free tool for ripping and converting video on your computer. This free video converter could function as a good Mac MP4 to AVI Converter to convert MP4 to AVI formats with faster speed and better quality. It can also convert among any kinds of video source for users to enjoy on all popular mobile players including iPad, iPod, Apple TV, PSP, etc. To convert MP4 to AVI on Mac with Handbrake, see below simple tutorial. 1. Download and launch Handbrake, click on the "Source" button to open a new window on screen to load MP4 files. 2. In the Destination section you can set the output folder by clicking Browse button. 3. Choose AVI format in Output Settings section and then click the green "Start" button at the very top of the main Handbrake window to do the MP4 to AVI conversion task.   However, people should notice that Handbrake is certainly not the easiest, most efficient converter program out there. Sometimes the process may break for some reason during the video conversion. But it is still the great ways to get MP4 movies better demonstrated on AVI Compatible Player including Mobile AVI Player.