Which website has the correct o.d of the duratrac tire

I looked at the 33x12.50r15 duratracs on the Goodyear website and it said the overall diameter is 32.8" and I looked at other sites like tire crawler and they listed the overall diameter of the duratrac 32.5". That site is not the only one that has listed o.d 32.5". Which site is true about the o.d? The reason for this is I might be going with the duratracs and I want a tire that is the closest to a 33 as possible.

 

You're talking about 3/10 of an inch... They'll vary more than that as the tread wears down.

 

i was under the impression that a true flotation size such as the 33 12.50 where true in size to what is in the tire.

correct me if i'm wrong here..