Body size, overall apearence and way they walk/move,depth of chest, age of face, mass/ spread and length/score, and general potential of each age class to produce a given rack/score. All those factors and more including experience of seein alot of bucks and watching them grow over the years give you a pretty good guesstimation as to what age they are. However region and food need to be taken into acount too. I could never acturatly agea deer from texas nor could the average texan age a deer accuratly in WI without getting some experience first hand with the deer over some years.A deer in texas at5 1/2years old could look like a 3 1/2 WI buck so knowing your situations and deer potential for the region in which thedeer are in is very important to aging as well. WCL

I would guess that buck in your avatar to be about 4 1/2 I supose but its hard to tell from that pic. Potentially 3 1/2with excellent nutrition. WCL