About the NPS Calculator
This NPS calculator turns answers to the question “How likely are you to recommend us to a friend or colleague?” into a Net Promoter Score. Enter how many promoters (9–10), passives (7–8) and detractors (0–6) you have, or paste the raw 0–10 ratings from your survey export, and it returns the score, the share of each group and a plain-English rating.
It is useful for product managers, customer success teams and founders tracking loyalty over time or comparing segments. Because NPS from a small survey can swing a lot, the calculator also shows an approximate 95% margin of error so you can tell whether a change from one quarter to the next is real or just noise.
NPS ranges from −100 (everyone is a detractor) to +100 (everyone is a promoter). Passives count towards the total number of responses but not towards the score, so converting passives into promoters raises NPS as much as preventing detractors. The rating label uses a common rule of thumb (below 0 Negative, 0–29 Good, 30–69 Great, 70+ Excellent); it is not an official Bain or industry standard, and typical scores vary a lot by industry.
With the default inputs, the net promoter score is 45. Change any value above to recalculate instantly.
How to use the nps calculator
- 1Choose whether you have group counts or raw 0–10 ratings.
- 2Enter the number of promoters, passives and detractors, or paste the ratings.
- 3Read your NPS and the share of each group.
- 4Check the margin of error before comparing scores between surveys.
Formula and method
Respondents who answer 9 or 10 are promoters, 7 or 8 are passives, and 0 to 6 are detractors. NPS is the percentage of promoters minus the percentage of detractors, reported as a whole number between −100 and +100 rather than a percentage. Passives are included in the total but do not add to or subtract from the score.
The margin of error treats each response as +1 (promoter), 0 (passive) or −1 (detractor). The variance of that score is p + d − (p − d)², where p and d are the promoter and detractor shares, and the 95% interval is ±1.96 standard errors. This assumes a random sample of customers.
- p
- Share of respondents who are promoters (9–10)
- d
- Share of respondents who are detractors (0–6)
- n
- Total number of responses
Worked examples
200 responses: 120 promoters, 30 detractors
Promoters make up 120 ÷ 200 = 60% and detractors 30 ÷ 200 = 15%, so NPS = 60 − 15 = 45. With 200 responses the 95% margin of error is about ±10 points.
Twelve raw ratings from a survey export
Six ratings are 9 or 10 (promoters), three are 7 or 8 (passives) and three are 6 or lower (detractors). NPS is 50% − 25% = 25, though with only 12 responses the margin of error is very wide.
More detractors than promoters
Half of the 200 respondents are detractors and only 20% are promoters, giving an NPS of 20 − 50 = −30. Even allowing for the ±11-point margin of error, the score is clearly negative.
Frequently asked questions
How do you calculate NPS?+
Ask customers how likely they are to recommend you on a 0–10 scale. Subtract the percentage who answered 0–6 (detractors) from the percentage who answered 9–10 (promoters). For example, 60% promoters and 15% detractors gives an NPS of 45.
What is a good Net Promoter Score?+
Any score above 0 means you have more promoters than detractors. Scores above 30 are often described as strong and above 70 as exceptional, but these bands are informal conventions rather than an official standard, and averages differ widely by industry, so compare yourself with direct competitors and your own past results.
Why don’t passives count in NPS?+
Passives (7–8) are satisfied but not enthusiastic, so they are treated as neutral. They still count in the total number of responses, which means a large passive group pulls the percentages of promoters and detractors towards zero.
How many responses do I need for a reliable NPS?+
The margin of error shrinks with the square root of sample size. With about 100 responses it is often ±10 to ±15 points; you need several hundred responses to detect a change of a few points with confidence.
Is NPS a percentage?+
No. Although it is calculated from percentages, NPS is reported as a plain number from −100 to +100. An NPS of 45 is written as 45, not 45%.