Icon resolutions: Pixels vs DPI

Question

When I try to do some research on making icons for Windows, and what size/resolution images I should leave in my .ico files before saving, there's too much weird information.

Some say put 16x16, 24x24, 32x32, 48x48 ... and so on in 96 DPI.

This is what irks me, and I feel it doesn't make any sense.

Isn't 1 pixel = 1 pixel?

Why do they insist on mixing DPI into this?

Answer 1

What is always true is that 1 pixel = 1 pixel . What does change is how big that pixel is one various displays that have different screen densities. That is what DPI describes - number of dots (pixels) per inch. But using DPI in context of image size only makes sense when you use it in combination with inches (centimeters). For instance "create image 10x10 inches at 300 DPI" and from that statement you can calculate that image has to be 3000x3000 pixels in size.

As far as Windows is concerned what does count is font scaling setting that can be set from 100% to 200%

So when you are creating your icons make sure that you have at least 1x and 2x dimensions. If the icon has to be 16x16 pix under normal resolution, that means that you would also create 32x32 pix icon. Other commonly used scaling are 125% and 150%, so it would be good idea to provide icon for those sizes too.

You can freely ignore statements like "Make the icon x pixels wide and x pixels high in x DPI" because those people have no clue what they are talking about.