Good evening, Growers!
This question comes up every year. Is there a way to estimate the weight of a giant pumpkin based on its physical measurements? Yes there is. Mr. Len Stellpflug the creator of the weight estimating table for giant pumpkins, has given us his permission to use the latest version of his spreadsheet. It can be found at: http://pumpkinnook.com/giants/weight.htm
The most accurate method is called the Over The Top Method or OTT Method. Measurements are taken from stem end to blossom end (front to back), from side to side, and then the circumference at the pumpkin's widest point. These three measurements are then added up and compared to Len's weight estimating table.
You'll see that this is the 2005 version. Len retired from competitive vegetable cultivation, so the 2005 version is the latest.