You can access Resizeimage.net to crop, resize and optimize GIF, JPEG and PNG images, it's handy if you want to resize your gifs to a smaller size and use it as your avatar icons on other sites, or crop your images to a specific size( e.g. 1366x768 px ) and use them as your desktop wallpapers, Facebook cover photos, PInterest profile pictures, iPhone wallpapers, etc.