You will need

a survey tool


1 week – 1 month


at least 1 person


1 – depending on the means of data collection

Use when...

  • you need to get an idea of users’ perception of your service as a whole
  • you want to compare your service with the competition
  • you have sufficient amount of users of your service

Do not use when...

  • you have just started your service (you can focus on testing of specific aspects of the service)
  • having a small number of users 


  1. Prepare an appropriate formulation of the question. The original formulation of the NPS is: “How much likely are you to recommend (company/product/service...) to your friend or colleague?”
  2. Prepare a tool where you can ask your users to send their answers. You may use online questionnaire. The question can also be asked by an employee who is in contact with the users on the daily basis.
  3. Users responses are measured on the scale from 0 (completely unlikely) to 10 (very likely)
  4. Count the percentage of those who chose options 0-6 - these are your disloyal users.
  5. Then count the percentage of those who chose options 9-10 - these users are the most loyal to your brand or service.
  6. Deduce the value of the number of disloyal ones from the number of loyal ones. The result is the NPS value.
  7. You can compare the NPS value with your competition or monitor its development over time. 

Keep in mind that...

  • online questionnaire tools often include ready templates for NPS measuring
  • another alternative to NPS is a continuous measuring of customer satisfaction
  • it is mostly good news when your result is over 50, it may, however, be very much dependent on the type of the service

Find out more

In the testing phase, you can use the following methods…

When you want to find out what is the current state of your service

When you need to decide which version of the service should be deployed

When you want to find out why the users stop using your service

Download the book Service Design in Libraries

It includes detailed descriptions of case studies from both the Czech Republic and Norway.

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You will always have a ready help, which will tell you how to proceed, and which tools to prepare.

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