Loyalty and satisfaction metrics

Net Promoter Score (NPS): calculation and interpretation

Net Promoter Score (NPS) is the gold standard for measuring customer loyalty and predicting organic growth.

It is based on a single question: "How likely are you to recommend our brand to a friend or colleague?", with a scale from 0 to 10.

Responses classify customers into three groups: Detractors (0-6), who are dissatisfied and may damage the brand; Passives (7-8), who are indifferent and vulnerable to competition; and Promoters (9-10), enthusiastic loyalists.

The index is calculated by subtracting the percentage of detractors from the percentage of promoters.

A high NPS (above 50 or 70) indicates excellent customer relationship health and high potential for expansion through word-of-mouth, while a low score indicates urgent structural problems.

Repeat purchase and retention rates

Beyond what customers say (as in NPS), what really matters is what they do.

Repeat purchase rates are a direct behavioral indicator of satisfaction and loyalty. If a customer buys again, they are validating the value proposition with their money.

Analyzing how often users return and buy the same product or purchase new services allows you to identify consumption patterns and brand stickiness.

An increase in retention rate is often more profitable than acquiring new users, as loyal customers tend to spend more and are more forgiving of occasional mistakes.

Post-sales satisfaction assessment

To get a granular view of the customer experience, satisfaction surveys (CSATs) focused on specific interactions are used.

These surveys, sent after a purchase or support interaction, ask about product quality, speed of service or clarity of information.

Unlike the NPS which measures overall loyalty, the CSAT helps to detect timely operational friction.

Analyzing this feedback allows companies to correct tactical failures, such as a confusing instruction manual or a slow returns process, closing the continuous improvement loop and ensuring that the post-purchase exper