Product-Market Fit Score

A survey-based metric that asks users "How would you feel if you could no longer use this product?" The percentage answering "Very disappointed" indicates product-market fit strength.

Also known as: PMF score, Sean Ellis test

Why It Matters

Created by Sean Ellis, this metric gives you a direct measurement of product-market fit. If 40% or more of your users say they would be "Very disappointed" without your product, you have strong product-market fit.

Unlike NPS which measures general satisfaction, the PMF score measures dependency and irreplaceability - how critical your product has become to users' workflows.

How to Calculate

Survey active users with the question: "How would you feel if you could no longer use [product]?" Options: Very disappointed, Somewhat disappointed, Not disappointed, N/A. The PMF score is the percentage who answer "Very disappointed."

Industry Benchmarks

Above 40%: strong product-market fit, safe to scale growth. 25-40%: promising but needs iteration. Below 25%: significant product improvements needed before scaling.

Common Mistakes

  • -Surveying all users including those who signed up but never activated
  • -Not segmenting by user type - you may have PMF with one segment but not others
  • -Treating 40% as a binary threshold rather than a signal to investigate further

Pro Tips

  • +Ask the follow-up: "What is the primary benefit you get?" to understand your core value
  • +Segment responses by user profile to find your highest-PMF segments and double down
  • +Re-measure quarterly as your product and market evolve

Related Terms

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