Forget size charts they is no accuracy and there is no such a thing, the weight of an animal depends on weight straight out of the egg, prey size, feeding frequency, how fast the animal is started and food refusal.

For example a healthy animal that hatch at 40 grams, starting to eat 4 weeks after hatching, getting started on large fuzzy to small hopper would be a lot smaller at 4 months than an hatchling hatching out at 90 grams starting to eat a small adult mouse the day after they hatch.

What matter is overall body condition / proportion and the fact that the animal actually eat.