I'm suprised I couldn't find any info on this.

The glasses seem to be divided into (or can be divided into):
Small
Small - medium
Medium
Medium - large
Large

Has anyone done any actual measurement (like circumferance) to figure out what group their noggin's in?

7 5/8" for me. witch is in the large catagory.

Q

I fall into the 7 1/4" category, WHICH is normal for people of incredible intelligence and physical apptitude!

yah, but you know what they say about guys with big heads!

Q

I think I can now officially say Ginormous (and 5/8")....

Ginormous here too...

Depending on hair length 7 1/8 to 7 1/4

another ginormous head here...

I fall into the 7 1/4" category, WHICH is normal for people of incredible intelligence and physical apptitude!

I can only second that.

I feel that small to medium glasses suit me best. But that is discussable and a matter of taste as well. Juliet and Gascan S are 'bout the largest I find appropriate for me. But to be honoust, I find the lens-colour to be of influence on the optical-size as well. Whisker Black lens looks better than Whisker Transitions.
So size doesn't always matter.....

I;ve got the biggest head here... who cares? still love the O!

Actually I think I have the biggest head here 8+". I love the O too, sometimes I just wish the O loved me as much.

how do u measure anyway?
i used a flexible measurement tape and wrapped it around my head and got 24 inches exactly.
enlighten me

For me it's the size of a fitted baseball cap. Don't know on measuring with a measurement tape.

I'm 7 5/8 which I always thought was pretty dang big, but I guess not ridiculous. I must have a wide face or something because most O stuff is too small for me.

I think the cap sizes are diameter, so divide your circumference by pi to get a rough estimate of your hat size.

can u calculate for me. 24 inches. must be smaller than average here since i forgot how to calculate.
i dont use much theorem or algebra or much maths nowadays except for simple calculations. heh

I've a small-medium head but I can fit GC and MD cause I curved the earstems by heating them on fire. And they seem to keep the shape until now.
notice that they are matte black and polished black (no coating for both).
I also "hammerized" the stems of my Square wire 2 SH, so they are nearer the head and the springs make more pressure