What category is my 3 point hitch?

There are four different hitch sizes, called categories. The higher category hitches have sturdier lift arms and larger connector pins. There is some flexibility in the tractor hp at which one category hitch ends and the next begins.

CategoryTractor HPTop Link Pin DiameterLift Arm Pin Diameter
0Up to 205/8 in5/8 in
120 to 45-553/4 in7/8 in
245-55 to 90-951 in1⅛ in
390-95 and up1¼ in1 7/16 in