NPS Formula
Subtracts the percentage of detractors from the percentage of promoters.
NPS = (promoters − detractors) ÷ all responses × 100
Worked example: (50 − 20) ÷ 100 × 100 = 30.
Why it matters
Passives count in the total, but not in the subtraction, which often surprises people.
How to use it
- Promoters answer 9 or 10.
- Passives answer 7 or 8.
- Detractors answer 0 to 6.
Example
50 promoters, 30 passives and 20 detractors out of 100 give an NPS of 30.