<s>[INST] What is a good, free way to scale a large batch of images down? They are of different sizes with the same aspect ratio. The target size is all going to be the same dimensions. [/INST] There are many ways to scale down images in large groups. 
You will may be able to find a free service online that will convert large batches of images, but upload and download times will slow you down. 
I would instead, recommend using a free offline software such as GIMP which works on Windows, Linux and Mac. 

You can download GIMP here:
https://www.gimp.org/downloads/ 

Would you like help installing GIMP on your computer?</s>\ <s>[INST] I said BATCH of images, not one image [/INST] You can use the program ImageMagick for that. ImageMagick is a free and open source program that offers the command line program `convert`. `convert` can apply multiple transformations to an input file, including resizing. By using a shell script, you can apply `convert` to multiple images with one script.</s>