The Mom Test
It's called The Mom Test because it leads to questions that even your mom can't lie to you about.
The Mom Test is Rob Fitzpatrick's prescriptive methodology for running customer interviews that surface truth instead of validation. Most founders unknowingly design interviews that invite polite agreement rather than honest feedback — The Mom Test provides a concrete ruleset for fixing that. By focusing on past behaviors instead of hypothetical opinions, and commitments instead of compliments, you learn what customers actually do rather than what they wish they might do.
“I think restaurant owners spend too much time manually tracking inventory and end up over-ordering or running out of popular items during service.”
Ask questions so good even your mom can't lie to you
The Mom Test is built on a foundational distinction: opinions about the future are worthless, but past behaviors reveal truth. Fitzpatrick's Three Core Rules — talk about their life instead of your idea; ask about specific past behaviors, not hypothetical futures; talk less and listen more — provide a concrete filter for every question you design. The methodology distinguishes compliments (empty noise that feels like validation) from commitments (time, money, or reputation staked on the problem being real), and provides a five-part conversation structure for framing discovery sessions. Fitzpatrick also introduces a note-taking shorthand organized around facts, emotions, and commitments, and establishes a test for whether a conversation was valuable: did it end with an advancement or a next step?
Most founder customer interviews are fatally flawed: they ask hypothetical questions ('Would you use this?', 'Do you think this is a good idea?') that allow polite people — including your own mother — to validate bad ideas out of social kindness. The result is a pipeline of false positives: customers who seemed enthusiastic in interviews but won't pay when the product ships. Founders mistake compliments for signal and spend months building for a market that doesn't exist.
The Mom Test skill stress-tests every interview question against Fitzpatrick's rules before you walk into the room, so you come out with facts about what customers actually do — not opinions about what they wish they might do.
- Your product hypothesis or the problem you believe exists
- Draft interview questions you've written (optional, for auditing)
- A transcript or notes from a past customer conversation (optional)
- The specific customer segment you're targeting
- A complete Mom Test-compliant interview guide tailored to your specific hypothesis
- A red/green audit of your draft questions with concrete rewrites for each violation
- A commitment-tracking framework to evaluate real signal across multiple conversations
- A diagnostic of where past interviews went wrong and what to ask instead
Watch the methodology work.
Three specimens from a single real session: the same situation, unaided and calibrated, the full transcript, and the skill answering live in the channel where the work happens.
“You've written ten interview questions: 'Would you use a tool that did X?', 'How much would you pay for this?', 'Do you think inventory management is painful?' You run five customer meetings, everyone says 'that sounds really interesting, keep me posted' — and you walk out convinced you've validated the idea.”
“Every question in your guide is a behavioral probe: 'Walk me through the last time that happened.' After five interviews, you know exactly how three owners currently handle inventory, which one abandoned a spreadsheet system after a costly failure, and that two are willing to be paid pilot partners. You know which pain is real and which was politeness.”
The same skill, where the work happens.
No new app to learn. The methodology runs over the WhatsApp Business API, so the answer lands as a reply in the thread you’re already in — same rigour, zero context-switch.
What it does, specifically.
Each capability is a distinct move drawn straight from the source methodology — not a generic assistant guessing.
Interview Question Auditor
Submit your draft interview questions and receive a line-by-line audit against The Mom Test's Three Core Rules. Each question is flagged as compliant or violating, with a specific explanation of what rule it breaks and a rewritten version you can use instead.
Mom Test Interview Guide Generator
Provide your hypothesis and target customer segment, and receive a complete, structured interview guide: conversation framing language, sequenced behavioral questions, probes for emotional intensity signals, and a closing sequence that solicits commitment advancement and referrals.
Commitment Signal Evaluator
After a customer conversation, describe what happened and receive an assessment of whether you got real signal. The evaluator distinguishes the three commitment currencies from compliments and fluff, and tells you whether the meeting constituted a genuine advancement.
Fluff vs. Signal Roleplay
Practice your interview in roleplay mode, where the skill plays a realistic customer who gives plausible but often empty responses. Learn to identify genuine pain signals — emotional intensity, unprompted returns to a topic, sighs — versus polite noise that feels like validation but predicts nothing.
Transcript Debrief & Diagnosis
Paste a transcript or notes from a real customer conversation and receive a structured diagnostic: where did you slip into opinion-fishing? Where did a customer signal real pain and you moved past it? What follow-up probes did you miss? What did you actually learn vs. what felt like learning?
Graded before it shipped.
Every skill is scored against independent scenarios for methodology fidelity before it goes live — not vibes, a rubric.
Mom Test Interview Script
A complete, hypothesis-specific interview guide with framing language, sequenced behavioral questions, emotional intensity probes, and a closing sequence that solicits commitment and referrals. Ready to use in your next customer conversation.
Question Audit Report
A red/green analysis of your draft questions — each flagged as Mom Test-compliant or violating, with the specific rule being broken and a concrete rewritten version you can use instead.
Commitment Signal Log
A structured record of commitments gathered across multiple customer conversations, categorized by currency type (time / money / reputation) — making the real signal in your discovery campaign visible and comparable at a glance.
Behavioral Fact Sheet
A structured notes template using Fitzpatrick's facts/emotions/commitments shorthand, capturing what customers actually do (not what they say they'd do), how they feel about it, and what they're willing to stake on the problem being real.
Grounded in the original work.
Every answer traces back to a real source and the practitioner who wrote it — not a secondhand summary. Here is the source of record.
Rob Fitzpatrick
Rob Fitzpatrick is a serial entrepreneur and startup educator whose customer development framework has become foundational curriculum at Y Combinator, startup accelerators, and entrepreneurship programs worldwide. He developed The Mom Test after observing that most founders conducted interviews specifically designed — if unintentionally — to confirm their assumptions rather than challenge them. The book is now widely regarded as the definitive guide to non-biased customer conversations.
The Mom Test: How to Talk to Customers & Learn If Your Business Is a Good Idea When Everyone is Lying to You
Serial entrepreneur; author of The Mom Test; customer development curriculum used at Y Combinator and leading global accelerators.
Put it to work.
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