Net Promoter Score (NPS) is a customer loyalty metric that measures the willingness of customers to recommend a company's products or services to others. It is based on the question, "On a scale of 0-10, how likely are you to recommend our product/service to a friend or colleague?"

Customers who respond with a score of 9 or 10 are considered "promoters," as they are likely to recommend the company to others. Customers who respond with a score of 7 or 8 are considered "passives," as they are satisfied but not necessarily loyal to the company. Customers who respond with a score of 0-6 are considered "detractors," as they are unlikely to recommend the company and may even discourage others from using its products or services.

The Net Promoter Score is calculated by subtracting the percentage of detractors from the percentage of promoters. The resulting score ranges from -100 to +100, with higher scores indicating higher levels of customer loyalty.

The Net Promoter Score has become a widely used tool for measuring customer satisfaction and loyalty, as it provides a simple and standardized way to track customer feedback over time. Companies can use the score to identify areas for improvement, prioritize customer service efforts, and benchmark themselves against competitors.