Glossary
Net Promoter Score
What is Net Promoter Score?
Net Promoter Score (NPS) is a customer loyalty metric based on a single question: 'How likely are you to recommend [product/company] to a friend or colleague?' on a 0-10 scale.
How it works
Respondents are classified as
- Promoters (9-10),
- Passives (7-8),
- or Detractors (0-6).
NPS is calculated as the percentage of Promoters minus the percentage of Detractors, yielding a score from -100 to +100. Fred Reichheld introduced NPS in 2003 as a growth-related metric. Its simplicity is appealing, but the score itself provides no diagnostic information about why customers are satisfied or dissatisfied, the single number conflates very different sentiment patterns, and cultural differences affect rating scales. Tracking it over time can raise questions for follow-up, provided changes in the sample and timing are considered.
A calculation
In a hypothetical survey of 100 respondents, 60 give ratings of 9–10, 25 give 7–8, and 15 give 0–6. NPS is 60% − 15% = 45. The 25 Passives remain in the denominator even though they are not directly added to or subtracted from the score.
Applied example
Suppose a software company records an NPS of 45 before a release and 30 afterward. Several respondents say they can no longer find the export feature in the redesigned navigation. Those comments give the team a specific task to investigate: observe people trying to export a file and check where they get stuck. The comments do not by themselves establish that the redesign caused the overall score decline; a different respondent mix or timing could also matter.
Why it matters
NPS summarizes stated willingness to recommend. For comparisons, consider sample uncertainty, audience, timing and context, and combine it with behavior and follow-up research.
Evidence note: Therese Fessenden: NPS alone does not diagnose causes or directly measure actual recommendations.