Your Net Promoter® Score (NPS) is calculated by subtracting the percentage of your detractors from the percentage of your promoters.
That’s as straightforward as it gets. NPS is fast to calculate, much like the standard NPS survey is extremely fast to take: all someone has to do is answer ONE question (‘how likely are you to recommend this product/company to a friend or colleague?’) by picking ONE number from 0 to 10.
But speed is not your main concern. NPS is often used as a predictor of business growth (or decline), so calculating it fast is less important than calculating it right.
NPS is calculated as the percentage of promoters minus the percentage of detractors, which only makes sense if you know what the ‘promoter’ and ‘detractor’ labels mean and how they get assigned in the first place.
What is a promoter in NPS
A promoter in NPS is anybody who answered the ‘how likely are you to recommend this product/company to a friend or colleague?’ question with a score of 9 or 10.
A detractor in NPS is anybody who answered the ‘how likely are you to recommend this product/company to a friend or colleague?’ question with a score between 0 and 6 (included).
They’re obviously not your biggest fans. But it’s worse than that: not only are they not likely to recommend you to others—they are the first candidates for leaving you and might even actively discourage other people away from your product. Clearly, one of your main goals is making sure you have fewer detractors.
What about passives?
Sat in the middle of detractors and promoters are the passives, who answered the NPS question with a score of 7 or 8. Technically, you should look at them as people who are ‘passively satisfied’ with your product or service but are not supremely loyal to it, which means they can be snatched away by the competition.
🏆Pro tip: passives are not included in the NPS calculation, but do not underestimate their importance. They are so close to being promoters, especially when they give you a score of 8, that any time spent investigating what you could do better/differently to win them over is time well spent.
3 NPS calculation methods
We’re going to take you through 3 main methods for calculating your NPS, using:
A spreadsheet/Excel, or
An online calculator, or
A survey tool with NPS feature
We’re also adding a bonus method by showing you the math behind NPS and how you can calculate it with pen and paper… should you ever want to!
We are going to use a real dataset from the last 30 days of our own NPS survey that got 563 responses:
How to calculate your NPS in Excel/Google Sheets
The Excel/spreadsheet method is best when your raw NPS data is just rows of numbers between 0 and 10 that need to be categorized as promoters, detractors, and passives:
2) Take your NPS survey results and input the number of responses into the calculator
3) Voilà: your NPS is displayed directly on the page!
How to calculate your NPS with a survey tool
If you collect your NPS data through a survey tool, it might already have an auto-calculate function built in that lets you get your NPS in one click—for example, Hotjar has this feature 😉
This is what the NPS question looks like in Hotjar:
And this is the result displayed in a dashboard:
The Hotjar NPS results dashboard
Two main benefits of using this method:
You don’t have to do any data exporting or copy-pasting, which saves you a little time and removes the potential for errors
Both the spreadsheet and the calculator give you a snapshot of the current situation; an NPS tool also helps you track changes, trace daily NPS fluctuations for the previous 30 days, and weekly/monthly fluctuations for the past 12 months.
Bonus method: the math behind NPS calculation
If you are interested in how NPS works—or if you ever find yourself wanting to calculate it with just pen and paper!—here is the math behind the calculation.
The promoters are counted by adding up the number of 9 and 10 responses (using the same dataset as the examples above, we have 238 + 80 = 318 promoters)
The same process is repeated for detractors, by adding up the number of responses from and including 0 to 6 (in our case, that’s 9 + 2 + 3 + 3 +7 +23 + 25 = 72 detractors)
The percentage of promoters is then calculated by dividing the number of promoters by the total number of responses (our dataset brings us to 318/563 = 0.56, or 56% when expressed as a percentage)
The same process is repeated for detractors, dividing the number of detractors by the total number of responses (for us, that’s 72/563 = 0.12 or 12%)
Finally, the NPS formula is applied: percentage of promoters minus percentage of detractors. (in our case: 56-12 = 44. And that is how you calculate your NPS manually!)
PS: there is more to NPS than just the number
NPS is a valuable metric on a strategic business level, but by itself, the score is not enough to paint a complete picture.
The value of doing an NPS survey is lost if you're not asking a follow-up question. If you don't ask customers why they've given you a specific score, then you're never going to truly understand what you're doing well and where you could be improving. And even if, overall, you have a relatively good score, you still need the qualitative insight to understand how to keep moving the needle and take things to the next level.
~ Emily Sergent, Director of Customer Experience at Hotjar
In other words: if you are running an NPS survey, don’t stop at the ‘how likely are you to recommend this product/company to a friend or colleague?’ question. Ask specific follow-up questions to empathize with your customers and understand the context behind their number.
For example, ask everybody who gives you 9 or 10 (promoter) “What’s the main reason for your score?”
Conversely, ask everybody who is a detractor/passive “What can we do to improve our business - and your score?”
And then look into the answers for trends every month/quarter, segment answers by customer types, report back to the team, and check back to see if your improvements have actually affected the score (if you want to see how we do it, you can read more in our 1st year using NPS blog post).
NPS is calculated as the percentage of promoters minus the percentage of detractors