To make the “perfect gob”, a correctly sized refractory orifice ring is required. With this online application the orifice ring size can be determined, by entering the glass container weight and adjusting the gob diameter to length ratio. The calculator has a weight range of 11g to 1701g. Charts give a range of different orifice ring sizes, but, will only allow to find the nearest weight to the actual gob weight. Why use charts and diagrams, when it is possible to calculate the required orifice ring size? Available for glassmakers from anywhere anytime via web browser – this calculator can help to make decisions faster. The calculator in the “Basic” mode is available for guests and registered users. There is also an “Advanced” mode of this calculator, for more details about the “Advanced” mode contact us at firstname.lastname@example.org.