NPS Calculator

Work out your Net Promoter Score from survey counts or raw 0-10 scores, with a margin of error

Updated 2026-10-02

Promoters (scored 9-10)

Passives (scored 7-8)

Detractors (scored 0-6)

Target NPS

Or paste raw 0-10 scores (overrides the counts)

Net Promoter Score: 45
95% range: 35 to 55 (±10.3)
Promoters: 60.0%
Passives: 25.0%
Detractors: 15.0%
Responses: 200
Promoters needed for NPS 50: 20 more

NPS = % promoters (9-10) − % detractors (0-6), from −100 to +100. Margin = 1.96 × √(((p + d) − (p − d)²) ÷ n) × 100. Promoters needed assumes no new detractors or passives.

Your numbers stay on this device. The page link keeps your inputs, so a bookmark or shared link reopens these results.

Type in how many customers answered 9-10, 7-8 and 0-6 on "How likely are you to recommend us?", or paste the raw scores straight from your survey export. The calculator gives the Net Promoter Score, the share in each group, a 95% margin of error for the sample size, and how many more promoters it would take to reach the score you are aiming for. Scores you paste never leave the page.

The Net Promoter Score formula

Customers answer one question on a 0 to 10 scale: how likely are you to recommend us to a friend or colleague? Those who answer 9 or 10 are promoters, 7 or 8 are passives, and 0 to 6 are detractors. NPS is the percentage of promoters minus the percentage of detractors, so it runs from -100 to +100 (Bain & Company, netpromotersystem.com, checked 2026-10-02).

With 120 promoters, 50 passives and 30 detractors out of 200 responses, promoters are 60%, detractors 15%, and NPS = 60 - 15 = 45. Passives count in the total but not in either percentage, which is why moving a passive to a promoter raises the score and moving one to a detractor lowers it.

Worked surveys (score, 95% margin of error, extra promoters to reach the target)
Promoters / passives / detractors	NPS	± margin	To reach
120 / 50 / 30 (200 replies)	45	±10.3	50: 20 more promoters
40 / 30 / 30 (100 replies)	10	±16.3	30: 29 more promoters
4 / 2 / 2 (8 replies)	25	±57.5	Too few replies to read

How much to trust the score

An NPS from a small survey swings a lot. Each reply counts as +1, 0 or -1, so the margin of error is 1.96 × √(((p + d) - (p - d)²) ÷ n) × 100, where p and d are the promoter and detractor shares and n is the number of replies. For the 200-reply example that is ±10.3 points: the true score is likely somewhere between about 35 and 55.

So a move from 42 to 45 between two monthly surveys of 200 people is noise, not progress. Track the trend over several waves, or survey more customers, before celebrating or panicking.

Ask at a consistent moment (after delivery, after a support ticket closes) so the waves compare like with like.
Read the comments from detractors first: they say what to fix. Passives say what would make them promoters.
Compare against your own past scores. A score from a different survey method or a different customer group is not a fair benchmark.

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Frequently asked questions

How do you calculate NPS?

Subtract the percentage of detractors (scores 0-6) from the percentage of promoters (scores 9-10). 60% promoters and 15% detractors give an NPS of 45. Passives (7-8) count in the total only.

What is the range of a Net Promoter Score?

From -100, when every respondent is a detractor, to +100, when every respondent is a promoter.

Is NPS a percentage?

No. It is the difference between two percentages, written as a whole number. An NPS of 45 is not 45%.

How many responses do I need?

There is no fixed minimum, but the margin of error shrinks with the square root of the sample. 200 replies give roughly ±10 points in the example above; 8 replies give about ±57, which tells you almost nothing.

Can I paste scores from Google Forms or a spreadsheet?

Yes. Paste the column of 0-10 answers separated by spaces, commas or new lines. Anything that is not a whole number from 0 to 10 is ignored and counted as invalid.

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