NPS Confidence Calculator
NPS is a difference of two proportions (% promoters − % detractors), and with a small sample it can swing a lot more than it looks like it should. This shows the real margin of error for your NPS, and how many responses you'd actually need to trust it. Nothing here is sent anywhere; it runs entirely in your browser.
Your current NPS
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How many responses do you need?
Assumes the promoter/detractor split above — or override to plan ahead.
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responses needed