PictureSizer for Ebay is an application designed to simplify the sizing of pictures of items to be sold to eBay.
Recent eBay changes put constraints on the pixel size of images for uploading.
Drag your images into PictureSizer and you will be able to rotate them and crop the images where necessary.
Press Save and Quit to overwrite the original images with resized ones. The size of the resulting images will depend on the Quality you have selected, Minimum, Better or Best.