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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
Calculator

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.

Margin of error (95%)In NPS points. The true score is likely within this range.±6.9
Promoters52.5%
Passives35.0%
Detractors12.5%
Responses400
Runs entirely in your browser. Nothing you type here is uploaded or stored by TapCub.

Share these inputs: the values go after the # in the link, so they never reach a server.

Version v1.0Updated Update history

Read the result

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.

How to use it

Three ways to use the calculator

Start from whatever your survey tool exports.

  1. 1

    From a summary report

    Most survey tools show counts per group. Type the promoters, passives and detractors.

  2. 2

    From raw answers

    Copy the score column from a CSV or spreadsheet and paste it. The calculator groups the scores for you.

  3. 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.

Formula

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

Worked example

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.

Example NPS by segment for one quarter
SegmentResponsesPromotersDetractorsNPSMargin (95%)
Customers who used live chat20065.0%10.0%+55±9.3
Customers who did not2,00052.5%17.5%+35±3.3
Enterprise accounts2065.0%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.

Common mistakes

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.

FAQ

Net 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?

NPS asks about the relationship and future recommendation. CSAT asks how satisfied someone was with a specific interaction. CES asks how easy it was to get something done. Many teams use NPS quarterly and CSAT or CES after each support case.

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.

Changelog

Update history

New features, fixes and data refreshes for this tool, newest first.

  1. · 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

Next step

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.

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