Free tool NPS calculator: Net Promoter Score and how to calculate it
NPS is the share of promoters minus the share of detractors. Enter the three group counts or paste the raw 0–10 answers, and get the score, the split and how far the score could move by chance.
- Counts or raw scores
- 95% margin of error
- Runs locally
Work out your NPS
Fill in the three counts, or paste the 0–10 scores from your survey export. If scores are pasted, they are used and the counts are ignored.
Respondents who answered 9 or 10. Enter 0 if none.
Respondents who answered 7 or 8. Enter 0 if none.
Respondents who answered 0 to 6. Enter 0 if none.
Separate with spaces, commas or new lines. Values outside 0–10 and non-whole numbers are skipped.
Net Promoter Score
+40.0
% promoters − % detractors, on a scale from −100 to +100.
Share these inputs: the values go after the # in the link, so they never reach a server.
https://tapcub.com/tools/net-promoter-score-calculator
Version v1.0Updated Update history
What the score tells you, and what it does not
NPS compresses a whole distribution into one number. Read it with the split and the margin of error, or two very different customer bases can look the same.
The score
Anything from −100 (everyone a detractor) to +100 (everyone a promoter). Above zero means more promoters than detractors. Track the direction over time rather than the level on its own.
Margin of error
With 400 responses the sample gives ±6.9 points: a +40 could really be anywhere from about +33 to +47. A change smaller than the margin is not yet a change.
The split
A +20 from 40% promoters and 20% detractors is a different business from a +20 with 25% and 5%. The first has many unhappy customers to fix; the second has many lukewarm ones to win.
Passives still count
Passives do not enter the subtraction, but they are in the total. More passives pull both percentages down and move the score toward zero.
NPS describes the people who answered. If only your happiest or angriest customers reply, the score describes them, not your customer base.
Three ways to use the calculator
Start from whatever your survey tool exports.
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1
From a summary report
Most survey tools show counts per group. Type the promoters, passives and detractors.
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2
From raw answers
Copy the score column from a CSV or spreadsheet and paste it. The calculator groups the scores for you.
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3
Before you compare
Check the margin of error. If two periods or two segments differ by less than it, collect more responses before you act.
NPS = % promoters − % detractors
Respondents answer "How likely are you to recommend us to a friend or colleague?" on a 0–10 scale. Scores of 9–10 are promoters, 7–8 passives and 0–6 detractors.
- Percentages use all responses, passives included, as the denominator
- The result is reported as a whole number of points, not a percentage
- Margin of error (95%) = 1.96 × √((P + D − NPS²) ÷ n), with P, D and NPS as proportions
NPS
NPS = (promoters − detractors) ÷ responses × 100
(210 − 50) ÷ 400 × 100 = +40
From raw scores
10 9 9 8 7 7 6 5 9 10
5 promoters, 3 passives, 2 detractors → (5 − 2) ÷ 10 × 100 = +30
Margin of error
1.96 × √((P + D − NPS²) ÷ n) × 100
1.96 × √((0.525 + 0.125 − 0.16) ÷ 400) × 100 ≈ ±6.9
Same score, very different certainty
One quarter of survey results split into three segments. The margin of error shows which scores you can lean on.
| Segment | Responses | Promoters | Detractors | NPS | Margin (95%) |
|---|---|---|---|---|---|
| Customers who used live chat | 200 | 65.0% | 10.0% | +55 | ±9.3 |
| Customers who did not | 2,000 | 52.5% | 17.5% | +35 | ±3.3 |
| Enterprise accounts | 20 | 65.0% | 10.0% | +55 | ±29.3 |
The enterprise score equals the live chat score, but with 20 responses it could be anywhere from about +26 to +84. The chat and no-chat gap (20 points) is larger than both margins combined. Sample figures.
Where NPS goes wrong
The subtraction is easy. The errors come from the survey and the reading.
Leaving passives out of the total
Dividing by promoters plus detractors only inflates both shares and exaggerates the score.
Tiny samples
With 20 responses the margin is close to ±30 points. A swing from +40 to +55 can be pure noise.
Changing when you ask
Asking right after a support chat and asking at renewal give different scores. Keep the trigger the same when you compare.
Skipping the follow-up question
The score says how many are unhappy, not why. Without an open "What is the main reason for your score?" you cannot act on it.
Where customer sentiment forms
Many promoters and detractors are made in a single conversation. TapCub’s live chat runs on the same visitor data as its analytics, so a support conversation is never cut off from what the visitor did on the site.
Live chat on the same data
Compare the people who chatted with the people who did not: conversion rate, order value and repeat rate.
Learn moreFirst response time
How long a visitor waits for the first reply from a person — the wait customers feel most.
Learn moreResolution rate
The share of conversations marked as resolved. Read it next to first response time.
Learn moreNet Promoter Score questions
Still have a question?
Chat with the team behind TapCub — we usually reply within a few hours on business days.
What is a Net Promoter Score?
A loyalty measure built on one question: "How likely are you to recommend us to a friend or colleague?" answered from 0 to 10. It was introduced by Fred Reichheld of Bain & Company in 2003. Net Promoter® and NPS® are registered trademarks of their owners.
How do I calculate NPS?
Group the answers: 9–10 promoters, 7–8 passives, 0–6 detractors. Subtract the percentage of detractors from the percentage of promoters. 210 promoters, 140 passives and 50 detractors give 52.5% − 12.5% = +40.
Is NPS a percentage?
No. It is the difference between two percentages, reported as points from −100 to +100. Write "+40", not "40%".
What is a good Net Promoter Score?
Scores vary a lot by industry, region, channel and the moment you ask, so a single benchmark misleads. A positive score means more promoters than detractors; beyond that, compare against your own past results collected the same way.
How many responses do I need?
It depends on how small a change you want to detect. With 100 responses the margin is typically ±12 to ±18 points; with 400 it halves and never exceeds about ±10. The calculator shows the margin for your numbers.
How is NPS different from CSAT and CES?
Why do the pasted scores override the counts?
Raw scores are the more detailed source, so the calculator groups them itself. Clear the text box to go back to the counts.
Update history
New features, fixes and data refreshes for this tool, newest first.
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· v1.0
LaunchedFirst release.
Missing something or found an error? Tell us — requests that come up often go into the next update. All tool updates
Fix the conversations behind the score
Detractors often come from a slow or unresolved support moment. Live chat on your site lets you answer while the visitor is still there.