I'm trying to figure the same thing out, lol. I just bought a scale today and posted the weights just now, lol. Yaddle is 17" long and weighed in at 461 grams. Not sure if she is overwieght though...
Yaddle looks like a perfectly healthy dragon, great size. My girl's tail is HUGE, she is 19" and 580ish grams. She is hefty but very healthy and muscly. Her vet asked if she was a body builder