Survey and customer feedback analytics
How to measure NPS (Net Promoter Score)
The short answer
Ask "How likely are you to recommend us to a friend or colleague?" on a 0 to 10 scale. Count 9s and 10s as promoters and 0 to 6 as detractors, then subtract the percentage of detractors from the percentage of promoters. The score runs from -100 to +100. The follow-up question ("What is the main reason for your score?") is where the useful information is.
Key takeaways
- NPS = % of 9s and 10s minus % of 0 to 6 answers, on a scale from -100 to +100.
- Small samples swing by ten points or more; read trends across several periods.
- The follow-up question is where the useful information is. Contact detractors quickly.
On this page 6 sections
Worked example
| Responses | Count | Share |
|---|---|---|
| Promoters (9 to 10) | 120 | 48% |
| Passives (7 to 8) | 80 | 32% |
| Detractors (0 to 6) | 50 | 20% |
| NPS | 48 - 20 = 28 |
When and where to ask
- Relationship NPS: a regular survey (quarterly or twice a year) to the whole customer base, by email or in the product.
- Transactional NPS: shortly after a specific event, such as delivery, onboarding or a support ticket.
- Do not survey the same person more often than every few months; response rates fall and answers get careless.
Sample size
Small samples swing a lot. With 50 responses, a handful of people changing their answer moves NPS by ten points or more. Look at trends over several periods and treat month-to-month moves with caution. Our A/B test calculator shows how much sample size matters for any percentage-based measure.
Closing the loop
- Tag open-ended answers by theme (price, support, a specific feature).
- Contact detractors quickly; a reply often recovers the relationship.
- Ask promoters for a review or referral while the goodwill is fresh.
- Report themes alongside the score, so the number leads to action.
NPS is one of three common loyalty measures. See NPS vs CSAT vs CES for when the others are a better fit.
Questions
- What is a good NPS score?
- Anything above zero means more promoters than detractors. Benchmarks vary widely by industry and by how the survey is run, so your own trend is a better guide than another company's number.
- Is NPS a percentage?
- No. It is the difference between two percentages, expressed as a number from -100 to +100.
Sources
Next step
Try the a/b test significance and sample size calculator
Related guides
NPS vs CSAT vs CES: which customer metric to use
NPS, CSAT and CES compared: the question each asks, how to calculate it, and when each one is the right measure of customer experience.
Product analytics vs web analytics: which one do you need?
The difference between web analytics (sessions and sources) and product analytics (users and events over time), with examples of the questions each answers.