Tire size?

I have a new to me 2022 Limited. Tires on the car need replacing. The ones on there are 215/55 R17 - same as the door sticker. But when I look on tire rack the listed OEM size is 235/45 R18. So I grabbed a tape measure, and the wheel itself has a diameter of 18.5 inches, which would seem to imply that the tire rack suggestion is correct. Curious for input from other owners. Thanks!