Measuring wheel width

[RedlineRacer]

I am sure this sounds stupid, but I have a reason for posting. When you measure the width of a wheel, do you measure the lip too? I bought a set of 16x7.5 wheels, and when I got them, I measured them, and they are 16x8. Do you measure with the lip?

[sxse240]

Wheel measurements are taken at the bead seat. That's where the bead of the tire actually mounts to the wheel, so it's measured inside. That's something I found out the hard way when my 18 x 9 -25mm wheels didn't tuck in under the fenders. My 9" wheel was 10.25" wide! Had I known that, I would have done things a little differently