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Nielsen Norman Group (nngroup.com)

1 resource from Nielsen Norman Group (nngroup.com) we point founders to, and the questions each answers.

✍️ Essay
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Why we picked it The honest answer to 'how many' is not a magic number, it is saturation: you keep going until new interviews stop teaching you anything new. This piece explains that idea plainly and gives a workable starting point (begin with about 5 to 6, then continue until the themes stop shifting), which is exactly the judgment call a founder is trying to make. Treat it as a rule of thumb to sanity-check your gut, not a quota to hit.

Interview Sample Size in Qualitative UX Research

From Nielsen Norman Group (nngroup.com) by Maria Rosala ~10 min read

  • Saturation is the real stopping rule: when the same jobs and pains keep repeating and fresh interviews add nothing, you can trust the pattern.
  • Start small (roughly 5 to 6) for a focused, similar group, and add more the moment answers start diverging.
  • The number depends on how varied your customers are and how broad your question is, so a wildly mixed audience needs more conversations than a narrow one.
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