Fotosizer is freeware to resize many images at once, or termed batch images resize software.
With Fotosizer, you can change the dimension of the photos (in large quantities) as well, so not wasted time. I found this software via Google Search when I will to change dimensions of my photos in large quantities and then uploaded for online personal photo album purpose. If allowed by the size of original photo, the upload process will take some considerable time.
Master installer capacity of Fotosizer just almost 2 MB, it is quite small. Its use is very simple. You can add folder or just few images of your choice, then press the Start button to start the process. To note is the Option on the part Resize Settings. There you can choose the dimension result, base on percentage from the original or pixel size. Remember to check option Reverse Width and Height by orientation, so the result are correct, not devastating your photographs dimension.
Another option to consider, Do not enlarge if smaller and Maintain aspect ratio. This options aims to not destroy the results of photos size change and the form of photos have similar proportion with original photo.
If you are interested to get Fotosizer, please read more on website.