Here's my handsome man. I just measured him, 8 inches from nose to tip of tail. Any clue how old he might be?
He could be anywhere from 3.5 to 6 months depending on his growth rate, parents, feeding, lighting, housing...
It appears he has bruises on him (the little black dots)
That leads me to assume he wasn't being housed alone before you purchased him and was getting stepping on by other chameleons.
Is he being housed alone now?