BWScaling Tool

What is Best–Worst Scaling?

Best–Worst Scaling (BWS) is a survey method where people see a small set of items at a time and choose which one is best (most important or most preferred) and which is worst (least important or least preferred). By repeating this across different sets, we can see which items matter most overall.

A very simple example

Imagine you want to know which pizza topping people like most. You have these four toppings: Pepperoni, Mushrooms, Onions, and Olives.

Instead of asking people to rank all four at once, you show them smaller sets of three toppings and ask them to pick the best and the worst in each set:

• Question 1: Pepperoni, Mushrooms, Onions — person picks Best = Pepperoni, Worst = Onions.
• Question 2: Mushrooms, Onions, Olives — person picks Best = Mushrooms, Worst = Olives.
• Question 3: Pepperoni, Onions, Olives — person picks Best = Pepperoni, Worst = Olives.

Across many people, we count how often each topping is chosen as best and as worst. If Pepperoni is picked as best very often and almost never as worst, it is clearly one of the most preferred toppings. If Olives are often chosen as worst, they are one of the least preferred.