NPS (Net Promoter Score) is an index that measures a customer's willingness to recommend a business, through a question: "From 0-10, how likely are you to recommend [brand] to a friend/colleague?". Scores 9-10 are Promoters (supporters), 7-8 are Passive (indifferent), 0-6 are Detractors (dissatisfied). NPS = % Promoter − % Detractor. Scores of 50+ are very good; Below 0 is dangerous. Zenify recorded a 21% increase in conversion rate (approved) for businesses tracking NPS periodically.
TL;DR
- NPS measures willingness to recommend: "How much would you recommend us?"
- Promoter (9-10), Passive (7-8), Detractor (0-6).
- NPS = % Promoter − % Detractor (on a scale of -100 to +100).
- ≥50 good, 0-50 acceptable, <0 dangerous.
- NPS must come with a "why" question — otherwise it's just a number.
What is NPS
NPS was developed by Fred Reichheld (Bain & Company) in 2003 — based on observation: customer referrals are the strongest loyalty signal. A single question, easy to answer, easy to compare.
Point classification:
Điểm | Nhóm | Ý nghĩa
9-10 | Promoter | Satisfied, will recommend, buy again
7-8 | Passive | Satisfied but easily manipulated by opponents
0-6 | Detractor | Unsatisfied, may say bad things
How to calculate NPS
Recipe:
NPS = (% Promoter) − (% Detractor)
Example: 100 customers responded. 60 guests scored 9-10, 25 guests scored 7-8, 15 guests scored 0-6.
NPS = 60% − 15% = 45
NPS scores range from -100 to +100, not 0-100.
How to read NPS
Mức | Ý nghĩa
50+ | Very good — strong customer support
20-50 | Good — has a loyal base
0-20 | Medium — much work to do
<0 | Danger — customers say more bad things than referrals
Note: NPS absolutely depends on the industry. NPS 30 of the insurance industry is good, but that of the e-commerce industry may be poor — compared to industry benchmarks, not general (see NPS benchmark by Vietnam industry).
Use NPS properly
1. Always include the question "why"
The NPS score doesn't say what you should fix — the open-ended answer does.
What Detractor said → that is something that needs to be handled with priority.
2. Measure periodically, not once
NPS by month/quarter to see trends — increases/decreases are more meaningful than single points.
3. Respond to Detractor immediately
Customers with low scores get called/messaged to handle → opportunity to save the relationship.
Not responding to Detractor is a wasted opportunity.
4. Include NPS in the process, don't leave "show numbers"
Low NPS in which service group → check that group's process.