A single question can gauge customer loyalty. Net Promoter Score, or NPS, asks customers how likely they are to recommend a company, product, or service on a scale from 0 to 10. Respondents who score 9 or 10 are promoters; those who score 0 to 6 are detractors; 7s and 8s are passives. The score is the percentage of promoters minus the percentage of detractors.

NPS is popular because it is simple to administer and to communicate. Companies track it over time and compare it with competitors or industry benchmarks. Follow-up questions about the reasons for the score supply the qualitative insight needed for improvement.

Critics note that the metric can be gamed and that it does not capture every dimension of customer experience. Supporters reply that its simplicity drives organizational attention to customer advocacy. When used as one indicator among others and linked to concrete action, NPS can help focus efforts on creating more promoters and fewer detractors.