Sweetness depends on the component. Across steviol glycosides it runs from about 150 to 350 times that of sucrose. Stevioside is around 150-250 times, Reb A around 180-350 times, and Reb M about 200-350 times, one of the sweetest components in the group.
The difference comes from molecular structure: the number of sugar units and where they attach change how strongly the molecule binds to the sweet-taste receptor. As a rule, the more sugar units a component carries and the closer its configuration is to Reb M, the higher the sweetness and the lighter the lingering bitterness.
Glucosylated steviol glycosides (GSG) are the exception: their sweetness is lower than Reb A, because the added glucose units raise molecular weight and reduce sweetness per unit of mass. What you buy in return is better solubility and a rounder mouthfeel - a deliberate trade of sweetness for quality.
A sweetness multiple is not a formulation factor
In sugar-reduction work this is the point that causes trouble: the multiple cannot be used directly to convert a formula. The measured sweetness of a steviol glycoside depends on the concentration of the sucrose reference it is compared against. Reb A 97, for example, measures about 350 times against a 2% sucrose solution but about 180 times against an 8% solution.
Acidity, flavourings and the food matrix interfere on top of that, so arithmetic conversion usually throws the taste balance off. Our recommendation is a gradient trial adjusted against the target sweetness curve.
Related products: Reb-A Series · Optimvia Reb-M / Reb-D