Before discussing how NPS translates into a star rating, it is important to understand that these two metric systems describe different things and are different calculations.
Net Promoter Score is used to help you understand customer sentiment towards your business and is designed to predict future company growth and health based on that sentiment. Because of this, the 0-10 scores provided by the customer are not just averaged together. Each promoter (9 and 10) counts as a plus one, each passive (7 and 8) counts as a zero, and each detractor (0 through 6) counts as a minus one. To arrive at the final score, we subtract the number of detractors from the number of promoters and divide that by the total number of scores.
The scores for NPS can range from -100 all the way to 100 so it is a 200 point scale. If you have more detractors than promoters, then you would have a negative NPS. It is weighted based on the groups of promoters, passives, and detractors in order to properly judge customer sentiment.
A star rating is simply an average of scores. The scores given by the customer are not weighted in any way.
Because the NPS rating and star rating are such different calculations, a conversion from NPS directly to star rating doesn't make sense. Instead, we can translate each individual 0 through 10 survey score into a comparable 1-5 score for the star rating. In the chart below, you can see how each response is translated.
NPS Rating | Star Equivalent
0 | 1
1 | 1.5
2 | 2
3 | 2
4 | 2.5
5 | 3
6 | 3.5
7 | 4
8 | 4
9 | 4.5
10 | 5
Now that we have converted each response to a 1-5 scale score, we can perform an average on these values and get a true star rating.
An example of the translated star rating can be seen on the Listen360 Public Reviews page. Each of the responses gathered by Listen360 is translated into the 1-5 score and listed at the bottom of this page. At the top of the page, you can see the aggregate or average star rating.
Additional Questions? Please reach out to Listen360 Support via email at firstname.lastname@example.org