For KPS EDI images we require your submissions to be no larger than 1080 pixels high by 1920 pixels wide (these are not interchangeable).
We have instructions on how to do this in a number of programs (click the links below).
The examples for our Photoshop resizing tutorial were created in Photoshop CS6 (thanks to Alfred Zommers).
The instructions work perfectly well with Photoshop CC despite looking a bit different. Tutorial is a printable PDF.
Luminar 3 This tutorial is a printable PDF.