NPS Calculator

This calculator turns the three response counts from a Net Promoter survey into the score, the promoter and detractor percentages, and a simple rating. Enter raw counts rather than percentages; the calculator works out the total for you.

NPS is used by customer-experience, product and support teams to track loyalty over time, compare segments, and link survey feedback to outcomes such as churn and repeat purchase. It is most useful as a trend and when read alongside the comments people leave, which explain why the score moved.

The score treats passives as neutral: they count toward the total but neither add nor subtract. That means turning a passive into a promoter raises NPS, and so does turning a detractor into a passive. Small surveys swing a lot by chance, so check the sample-size section before reacting to a change of a few points.

The method was introduced by Fred Reichheld of Bain & Company in the Harvard Business Review in 2003 and developed with Satmetrix; Net Promoter and NPS are their registered trademarks. The calculator's rating labels (50 and above "Excellent", 20–49 "Good", 0–19 "Needs work", below 0 "Poor") are a rough guide, not part of the official method.

If you have raw 0–10 scores, count them into the three groups first. Do not average the scores — an average of 8 can hide very different mixes of promoters and detractors.

Because NPS subtracts two percentages, it is noisier than a simple satisfaction percentage. The 95% margin of error is about 1.96 × √((P + D − (P − D)²) ÷ n), where P and D are the promoter and detractor shares and n is the number of responses. As a rule, a few dozen responses can only show broad direction; several hundred are needed to detect a change of 5 to 10 points.

• Detractor to passive: each one moves NPS up by 100 ÷ total responses. In a 315-response survey, that is about 0.3 points each.
• Passive to promoter: the same gain per person, and often easier, because passives are already satisfied.
• Detractor to promoter: twice the gain, but rare without a real change in product or service.
• Closing the loop: contacting detractors soon after they respond, fixing the issue and telling them what changed is the practice most associated with lasting improvement.

Scores differ widely by industry, country and survey method, so the most useful comparison is with your own previous results using the same question, timing and audience. Relationship NPS (asked periodically to all customers) is usually lower than transactional NPS (asked straight after a purchase or support contact). Changing the channel, adding incentives or surveying only active users will shift the score without any change in loyalty.