You've seen enough pictures of people holding them to get a good reference for the size.

I've owned one. But that was a million years ago. It's somewhere between the size of a box of matches and my current phone, but that's a pretty big range.

Edit: OK so maybe the reference of a gen 1 ipod is actually quite useful to me. But it's a 20 year old reference to use. Surely there are plenty of things around that are more useful as a reference point if you need one (or just provide measurements).

Since when could only rich Americans use image searches? Or are you just being facetious?

Let me Google that for you: https://images.app.goo.gl/hW7G3NaixUd4sNUc7

The iPod was about the size of a deck of cards but 50% thicker.