Free NPS calculator
Enter how many people gave each answer, or paste the raw scores. The score, the breakdown and the margin of error update as you type.
Free, no account needed. Updated .
Short answer
Net Promoter Score is the percentage of promoters (scores of 9 or 10) minus the percentage of detractors (scores of 0 to 6). It runs from -100 to 100. This calculator also shows the margin of error, so you can tell a real change from noise in a small survey.
How to use the NPS calculator
- Pick an input. Choose Enter counts if you already know how many promoters, passives and detractors you have. Choose Paste scores to paste the raw 0 to 10 answers from a spreadsheet or survey export.
- Enter the numbers. The score, the breakdown and the margin of error update as you type. Values that are not whole numbers from 0 to 10 are skipped and listed under the box.
- Read the margin of error before you compare. If this month's score is inside last month's margin of error, the change can be noise.
The calculator runs in your browser. Your numbers are never sent to a server.
The NPS formula
Net Promoter Score comes from one question: "How likely are you to recommend us to a friend or colleague?", answered on a scale from 0 to 10. Each answer goes into one of three groups:
| Score | Group | Counts in the score as |
|---|---|---|
| 9 or 10 | Promoter | Adds to the score |
| 7 or 8 | Passive | Counts in the total only |
| 0 to 6 | Detractor | Subtracts from the score |
NPS = % promoters − % detractors. The score runs from −100 (everyone is a detractor) to +100 (everyone is a promoter). It is a number of points, not a percentage.
A worked example
A support team sends the survey after each closed ticket and gets 200 answers: 110 promoters, 50 passives and 40 detractors.
- Promoters: 110 ÷ 200 = 55%.
- Detractors: 40 ÷ 200 = 20%.
- NPS: 55 − 20 = +35.
The 50 passives do not add or subtract, but they matter: they are in the total. If those 50 people had not answered, the score would be 110 ÷ 150 − 40 ÷ 150, which is about +46.7.
Why the margin of error matters
NPS from a sample is an estimate. The calculator gives each answer a value of +1 (promoter), 0 (passive) or −1 (detractor) and computes the 95% margin of error of the average. For the example above it is about ±11 points. So the true score is likely between +24 and +46, and a move from +35 to +38 next month says nothing on its own.
The margin shrinks with more answers, roughly with the square root of the count. Four times as many responses halve it. Small teams can still use NPS: compare quarters instead of weeks, and look at the comments behind the scores.
What is a good NPS?
Any score above 0 means more promoters than detractors. Beyond that, a fair comparison is hard. Scores change with the industry, the moment you ask (after a purchase, after a support ticket, once a year), the channel and who answers. A score from a post-ticket survey and a score from a yearly relationship survey measure different things.
The most useful benchmark is your own score over time, with the same question, the same moment and the same audience.
How to improve NPS from support
- Read the detractor comments first. Group them by cause. A few causes usually explain most of the detractors.
- Close the loop. Contact detractors, fix what you can and tell them what changed.
- Remove waiting. Slow answers to simple questions are a common cause of low scores. Write the answers to repeat questions in your help center, and make them easy to find on the page where people ask.
- Measure the same way every time. A change of method changes the score more than a change in service.
If repeat questions drive your tickets, a support chatbot that answers from your own help pages can take the simple ones and pass the rest to your team. If you want to see how many pages such a bot could read on your site, run the sitemap checker on your help center.
Frequently asked questions
How do you calculate NPS?
Ask "How likely are you to recommend us to a friend or colleague?" on a 0 to 10 scale. Count promoters (9 or 10) and detractors (0 to 6). NPS = percentage of promoters minus percentage of detractors. Passives (7 or 8) count in the total but not in either group.
What is a good NPS score?
Any score above 0 means you have more promoters than detractors. Averages differ a lot by industry and by how the survey is sent, so the most useful comparison is your own score over time, measured the same way each time.
Can NPS be negative?
Yes. NPS runs from -100 (every respondent is a detractor) to 100 (every respondent is a promoter). A negative score means detractors outnumber promoters.
How many responses do I need for a reliable NPS?
It depends on how precise you need the score to be. With 100 responses the margin of error is often 10 to 20 points; with 400 it is often 5 to 10. The calculator shows the margin of error for your own numbers.
Why does NPS ignore passives?
Passives are counted in the total number of responses, so they lower both percentages. They are not added or subtracted because the score is built to compare people likely to recommend you with people likely to warn others away.
Is my data sent anywhere?
No. The calculator runs in your browser. The numbers and scores you enter never leave your device.
Newsletter
Support notes, once a month.
One email with what we learn about help centers, honest AI answers and support teams. Unsubscribe at any time.