How to Calculate Net Promoter Score
Learn how to calculate NPS from survey responses, avoid common calculation mistakes, and interpret your score with context.
Short answer: To calculate NPS, subtract the percentage of detractors from the percentage of promoters.
How to Calculate Net Promoter Score
To calculate Net Promoter Score, collect responses to the standard 0 to 10 recommendation question, group responses into promoters, passives, and detractors, then subtract the percentage of detractors from the percentage of promoters.
The math is simple, but the measurement process matters. Survey timing, audience, sample size, and follow-up comments all affect how useful the score will be.
You can calculate your score instantly using the Net Promoter Score Calculator.
Step 1: Ask the NPS question
Ask customers the standard NPS question:
How likely are you to recommend our company to a friend or colleague?
Use a 0 to 10 scale and keep the wording consistent if you want to compare results over time.
- Use relationship NPS for overall loyalty.
- Use transactional NPS after a specific experience.
- Avoid changing the scale or labels between survey waves.
Step 2: Categorize responses
Group each response into one of the three NPS categories.
| Score | Category |
|---|---|
| 9-10 | Promoters |
| 7-8 | Passives |
| 0-6 | Detractors |
Step 3: Calculate percentages
Divide the number of promoters by total responses to calculate promoter percentage. Then divide the number of detractors by total responses to calculate detractor percentage.
Passives are included in total responses, even though they are not directly subtracted in the formula.
| Group | Count | Calculation | Share |
|---|---|---|---|
| Promoters | 50 | 50 / 100 | 50% |
| Passives | 30 | 30 / 100 | 30% |
| Detractors | 20 | 20 / 100 | 20% |
Step 4: Apply the NPS formula
Subtract detractor percentage from promoter percentage.
In the example above, the NPS is 50 minus 20, which equals 30.
Step 5: Interpret the score
A score above 0 means promoters outnumber detractors. A score above 30 is often strong, and a score above 50 is often excellent. But context matters: industry, customer type, survey timing, and your own historical trend all shape interpretation.
| Score | General interpretation |
|---|---|
| Below 0 | Needs attention |
| 0-30 | Positive, with room to improve |
| 31-50 | Strong |
| 51+ | Excellent |
Step 6: Read the comments
The NPS number is only the start. Open-ended comments explain what creates promoters, what keeps passives from recommending you, and what frustrates detractors.
Group comments into themes such as pricing, support, product quality, onboarding, delivery, billing, reliability, or communication.
NPS calculation checklist
- Use the standard 0 to 10 scale.
- Count every valid response once.
- Include passives in the total response count.
- Calculate percentages before subtracting.
- Report NPS as a number from -100 to +100.
- Compare results only when audience and survey method are similar.
What to do after calculating NPS
- Follow up with detractors where appropriate.
- Review passives for practical improvement opportunities.
- Study promoters to understand what creates advocacy.
- Share themes with the teams that can act on them.
- Track whether changes improve the score over time.
Related pages on Calculator for NPS
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Frequently Asked Questions
How often should you calculate NPS?
Many teams track NPS quarterly or continuously, depending on their customer feedback program.
What is a good NPS score?
Above 0 is usually positive, above 30 is strong, and above 50 is often considered excellent. Industry and survey context still matter.
Do you need individual 0 to 10 responses to calculate NPS?
No. You can calculate NPS from either individual ratings or grouped counts of promoters, passives, and detractors.
Should NPS be rounded?
Most teams report NPS as a whole number. If decimals appear, use a consistent rounding rule.