What Is the Sean Ellis Test?
The Sean Ellis test is a single-question survey that measures product-market fit:
"How would you feel if you could no longer use [product]?"Answer options:
- Very disappointed
- Somewhat disappointed
- Not disappointed
Why This Test Works
Sean Ellis analyzed hundreds of startups and found:
- Companies with 40%+ "very disappointed" consistently grew
- Below 40%, growth was a struggle
- The question captures emotional attachment, not just usage
How to Run the Survey
Who to Survey
Right audience:- Active users (used product 2+ times)
- Recent users (used in last 2 weeks)
- Experienced core value (not day-1 signups)
- One-time visitors
- Churned users
- People who signed up but never engaged
Sample Size
- Minimum: 40 responses for directional insight
- Reliable: 100+ responses for confidence
- Segmented: 40+ per segment if comparing groups
Survey Timing
- After users have experienced core value
- Not immediately after a positive/negative event
- Consistently (monthly/quarterly for tracking)
Additional Questions
Add these for actionable insights:
- "What type of person would benefit most from [product]?"
- "What is the main benefit you receive?"
- "How can we improve [product] for you?"
Interpreting Results
Score Ranges
- 0-20%: No PMF – Major pivot likely needed
- 20-40%: Approaching PMF – Iterate aggressively
- 40-60%: PMF achieved – Ready to scale
- 60%+: Strong PMF – Exceptional product
Segment Analysis
Overall score can hide insights:
- Slice by customer type
- Slice by acquisition channel
- Slice by use case
- Slice by company size
What If You're Below 40%?
Step 1: Find Your Best Segment
Which users ARE very disappointed? What do they share?
Step 2: Double Down
Focus exclusively on that segment.
Step 3: Understand the Gap
Interview "somewhat disappointed" users:
- What would make you "very disappointed"?
- What's missing?
- What almost works?
Step 4: Iterate and Retest
Make changes based on feedback. Survey again in 4-6 weeks.
Common Mistakes
1. Surveying Too Early
New users haven't experienced value. Wait until they have.
2. Small Sample Size
20 responses isn't enough. Get 40+ minimum.
3. Biased Distribution
Don't only survey your happiest users.
4. Ignoring Context
Score without segment analysis misses the story.
5. One-Time Measurement
PMF is a moving target. Track over time.
Limitations of the Test
What It Captures
- Emotional attachment
- Perceived value
- Switching cost (emotional)
What It Doesn't Capture
- Willingness to pay
- Actual retention behavior
- Growth potential
- Unit economics
Beyond the Survey
The Sean Ellis test is one signal. Also track:
- Retention curves – Do users actually stay?
- NRR – Do customers expand?
- Organic growth – Do users refer others?
- CAC payback – Are economics working?
The Origin Story
Sean Ellis coined "product-market fit" measurement while working as first marketer at Dropbox, LogMeIn, and Eventbrite.
He noticed that companies where 40%+ users would be "very disappointed" grew efficiently. Those below 40% struggled regardless of marketing spend.
The test became the standard PMF measurement across Silicon Valley.
What If Results Suggest a Pivot?
If your Sean Ellis score stays below 40% despite iterations:
- The problem might not be painful enough
- Your solution might not fit the problem
- You might be targeting the wrong customer segment
Related Reading
- What is Product-Market Fit? Complete Guide
- 7 Clear Signs You've Achieved PMF
- When No One Would Miss Your Product
- How to Measure PMF: Metrics & Frameworks
- Why 90% of Startups Fail Before PMF
Take Action
Want to know your Sean Ellis score and what to do about it?
Our PMF Assessment includes the Sean Ellis test plus 5 other PMF dimensions.
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