Sociolatte

To start of it is safe to say that the best format of video to upload to Facebook is the MP4 format. This is the easiest format Facebook can handle and it can be played and displayed on a variety of systems. Once you begin to upload a video on Facebook, several things begin to happen. The complete videos gets upload and this can take some time especially if your video is fairly large. Once you video has been uploaded the process of 'encoding' begins. So after your video has been uploaded onto Facebook's servers you will get the message ' Video is Encoding'. When you get the message that your video is being encoded it means that you video has been uploaded and now being converted into various formats. This happens to ensure that your video is available to anyone who wants to view it no matter what system or device they are using. So if someone has a really old PC with an outdated browser, it will still play in low quality. If you friend is checking out your video on their iPhone or Android phone it will play in the correct format for best viewing on mobile devices.


Facebook Video Processing or Encoding  is a fairly complex function and is done to ensure your videos are always avoidable to people on any system or any device. 


Where to find you're videos that are still encoding
Click on this link should take you to a list of your videos that are still being encoded.


How do i find a list of acceptable video formats to upload on Facebook
Clicking on this link will give you a list of video formats supported by Facebook. Also do remember that your best bet for most acceptable video format on Facebook is the MP4 format.