Net Promoter Score (NPS) is the customer loyalty metric calculated by subtracting the percentage of Detractors from the percentage of Promoters. Customers answer a single question, "How likely are you to recommend this product/company to a friend or colleague on a 0-10 scale?", with Promoters scoring 9-10 and Detractors scoring 0-6. The resulting number ranges from -100 to +100 and is used as the headline metric for customer loyalty and satisfaction. Developed by Fred Reichheld at Bain & Company in 2003, NPS has become one of the most-used (and most-criticized) customer metrics in business.
The math:
NPS = % Promoters (9-10) - % Detractors (0-6)
Passives (7-8) are excluded from the calculation but represent cus...