BleepingComputer.com: Why is my image file size BIGGER after I crop it?

Disclaimer: I'm trimming these with the common photo-viewing application "Preview" that is native on all Macs for the past however many years.

I have a series of images. They are in JPG format. They show up as occupying ~900kb each. I am trying to trim away the borders of these to clean them and save space in printing.

The program in which I view these files has selection and cropping tools. I select what I want, Ctrl+K to crop, image is trimmed neatly. Great.

When I save the files, however, the size balloons to roughly 1.8MB each. What the hell? I just REMOVED information by cropping the files. They are still .JPG files, same as they were before. What is increasing the file size? How can I get rid of that extra data? I have tried PNG lossless compression online (Smush.It), but could only remove ~100kb from each file.

Please help me. ;_;

It sounds as if the pixels per inch is being increased when you're cropping it. As I'm not familiar with Macs, see if there's an option that will allow you to lower the resolution (say to 150 ppi is way more than enough, although 100 ppi should be OK, too). Also, when you save it as a .jpg, see if there's an option that allows you to adjust the quality of the image being saved (usually it's a scale of 1 - 12, with 12 being the highest and 1 being the lowest...6 - 8 is usually a good size to save at without losing quality).

Also, adding filters or sharpening them (which some programs will do automatically unless told otherwise) will increase the file size.

It may be trying to save the cropped image at a higher quality level than the original.