rEASYze is an elegant and portable app that takes a fresh approach image resizing.
This handy little tool is wrapped around a dark or light-themed interface (your choice) that is easy on the eyes. It is able to process multiple pictures simultaneously, change their format, apply filters and watermarks, etc.
It it super lightweight, has a small footprint and can work with multiple images at the same time. So, if you need to resize some shots at no cost, then check out rEASYze.