How to find out frame rate (FPS) of an AVI video on OS X?

Solution 1:

With a recent version of VLC, go to the "Window" menu and choose "Media Information" (or press ⌘ I). If you have more than one video in your playlist, make sure the desired one is selected.

Switch to the "Codec Details" tab, then click to expand the details for each stream until you find the video stream. The frame rate is listed there.

The screenshot below comes from VLC 2.0:

Solution 2:

You could also use mplayer -identify -frames 0 file.avi.

Solution 3:

MediaInfo is a pretty comprehensive cross-platform tool for getting all sorts of information about pretty much any video format around.