Most companies I work with accept much larger photos than 640 x 480. Depending on how big they are, and how stable your internet connection is, may require you to shrink them.
Hands down the EASIEST program for resizing one or multiple photos at a time is Batch Picture Resizer 6.0. It is available from [
www.rw-designer.com]. You download this very small photo onto your desktop. You select all photos (or the folder your photos are in), and drag them onto the program. It quickly resizes them all to whatever you desire. The name of the program is "PhotoResize400.exe" You rename the "400" to whatever you want - 640, 1080, etc. It makes the photos 400x or 640x or 1080x or whatever you selected. It keeps the aspect ratio, so whatever it was before, it keeps true.
Takes seconds to resize hundreds or thousands of photos if required!