Could you give me a quick and clear summary of how to calculate NPS?

NPS Calculation is a simple equation that is calculated by subtracting the percentage of detractors from the percentage of promoters who have responded to a standard NPS (Net Promoter Score) question... but hang on, that sounds quite complicated.

(You might also find our interactive NPS Calculator useful, or full background to How the NPS calculation works.)

Let me explain these various elements, and I'll start with what is a standard NPS question: it's deceptively simple and is worded as:

Those viewing the survey question see a scale of 0-10 (where 0=not at all likely to recommend the product, and 10=extremely likely to recommend the product).

In the NPS methodology, responses are organized into three groups that are based on the scoring:

Scores of 0-6 are called detractors

Scores of 7-8 are called passives

Scores of 9-10 are called promoters

So, finally to your question: the NPS score is calculated by subtracting the percentage of detractors from the percentage of promoters; we ignore the passives for the calculation.

The NPS score is displayed as a number (not as a percentage) and can be within the range of -100 to +100.

Here's a worked example:

Let's take a look at how to calculate the NPS for responses to your survey over the course of a day. In this example, you've had 10 respondents and they have given your product the following scores:

3, 4, 5, 6, 8, 8, 8, 9, 10, 10

If we arrange these into detractors, passives and promoters, this equates to:

four detractors (3, 4, 5, 6), ie 40% of the responses

three passives (8, 8, 8), ie 30% of the responses

three promoters (9, 10, 10), ie 30% of the responses

So the day's NPS = -10 (calculated by: 30% promoters - 40% detractors = -10)