Measure around the complete circumference of the throat of the windsock. Take that measurement and divide by 3.14. This will give you the diameter of the windsock in inches. Also measure the length to determine the length.

Lay your windsock flat on a table or floor. Measure from one side to the opposite side of the throat. Take that measurement & multiply by 2, then divide by 3.14. The result will be the diameter of your windsock.

Measure from side to side through the middle of your windsock frame and the result will be the diameter of your windsock.