RightSize checks that .png, .jpg, .jpeg, .gif and *.webp files are the
size you expect.  By that I mean the size of the images in pixels, not the
size of the files themselves in bytes.  In particular, you might use it to
check that all your PAD icons are precisely 32x32, or screenshots are
between 200 x 200 and 800 x 600 or to find all the very large or very
small images in your collection.  It will also check that files are
consistent, e.g.  that you have not stored a gif file with a png
extension.  You can check single files, lists of files and even multiple
directory trees.  To check a single image file is between 32x32 and 64x64
inclusive , type:
  java.exe -jar C:\com\mindprod\rightsize\rightsize.jar 32 32 64 64  lemon.png
You can also list several files on the command line:
  java.exe -jar C:\com\mindprod\rightsize\rightsize.jar  32 32 64 64 pear.jpg C:\mydir\peach.gif
you can check an entire directory of files:
  java.exe -jar C:\com\mindprod\rightsize\rightsize.jar  32 32 64 64 .
Sorry no wildcards, just .  , and ..  DON'T USE WILDCARDS unless you
deeply understand how they work.  See
http://mindprod.com/jgloss/wildcard.html.  Windows expands them, not
RightSize, and feeds them to RightSize (or any other program) as a giant
list of all the directories and files in the current directory.  RightSize
will thus tend process all the files in your directories, when you just
meant to process the files in the current directory.
The -s switch makes all subsequent directories searched
recursively to include all their subdirectories.
e.g.  to check that all files in the directory tree in the size range 16x32 and 128x100
  java.exe -jar C:\com\mindprod\rightsize\rightsize.jar 16 32 128 100  E:\mindprod
If you have the jar extension set up as executable, you can
abbreviate:
  C:\com\mindprod\rightsize\rightsize.jar 16 32 128 100 .
If you have Jet that will collapse further to:
  rightsize.exe 16 32 128 100 .
It tells you only about the files out of range.  If all you want to do is
get a list of how big each image is, just ask for limits: 9999 9999 9999
9999 and every image will fail and tell you its size.
There is a companion utility called cropper that bulk crops images to a
desired size.
Why the bowl of porridge icon?  It is reference to the children's story
Goldilocks and three bears.  She tasted the three bowls of porridge, one
was too hot, one too cold and one just right.  RightSize makes sure images
are "just right" too.