Interviews · 13 min read

YC Interview Questions — Complete List of 100 Questions Asked

Short answer

YC interviews are 10 minutes. Two or three partners. No slides. No warm-up. The first question lands within seconds and the pace stays fast the entire time. Partners have a short list of things they want to confirm and a longer list of things they want to probe. Most questions fall into eight categories — and knowing those categories, and the exact questions asked within each, is the most direct preparation available.

How to Use This List

Do not memorize answers to all 100 questions. That produces robotic, over-rehearsed answers that partners immediately recognize. Instead: read the full list, identify the 6-8 questions in categories where your company has the most vulnerability, and practice answering those specifically until your answer is specific, confident, and under 45 seconds.

The goal is not to have a prepared answer for every question. The goal is to know your company so thoroughly that any question about it produces a clear, specific, honest answer within a few seconds.

Category 1: What Are You Building

These questions establish the baseline. Partners want to hear you describe your company in plain language — not pitch language.

1. What does your company do? 2. Explain what you do in one sentence. 3. Who is your customer? 4. What problem are you solving? 5. Walk me through what a user does on your product in a typical session. 6. What is the core workflow your product enables? 7. How does a customer first hear about you? 8. What does a new user experience in their first 10 minutes on your product? 9. Show me the product. 10. What would your best customer say about your product if I called them right now?

What partners are probing: clarity of thought and product understanding. Founders who cannot describe their product simply and specifically in under 30 seconds reveal confusion about what they are building. The simpler and more specific your answer, the more confident you appear.

Category 2: The Problem and Market

11. Why does this problem exist? 12. How big is this problem? 13. How many potential customers are there? 14. Why hasn't this been solved before? 15. What is the total addressable market and how did you calculate it? 16. Who else has this problem besides your current customers? 17. Why is this problem acute enough that people will pay to fix it? 18. What do people currently do instead of using your product? 19. How much does this problem cost your customer in time or money? 20. Is this a vitamin or a painkiller?

What partners are probing: market sizing judgment and problem depth. The worst answers cite a Gartner report. The best answers describe a specific number of specific users experiencing a specific measurable cost.

Category 3: Traction and Evidence

21. How many customers do you have? 22. What is your monthly revenue? 23. What is your month-over-month growth rate? 24. What is your retention rate? 25. How did you get your first customer? 26. What did your first 10 customers have in common? 27. What does your best customer look like? 28. What does your worst customer look like? 29. Have you lost any customers? Why? 30. What does a customer say when they cancel? 31. Who referred customers to you and why did they refer? 32. What would your customers do if you shut down tomorrow? 33. What is your CAC and how did you calculate it? 34. What is your LTV? 35. What is your payback period?

What partners are probing: the authenticity and depth of your traction. Know every number exactly. Partners will quote your application numbers back at you and probe any inconsistency.

Category 4: The Business Model

36. How do you make money? 37. What do you charge and why that price? 38. How did you arrive at your pricing? 39. What would happen if you doubled your price? 40. What is your gross margin? 41. What is your burn rate? 42. How much runway do you have? 43. When will you be default alive? 44. What would make this business default alive in the next 6 months? 45. How does revenue scale relative to costs?

What partners are probing: financial clarity and unit economics soundness. If you do not know your gross margin, your burn rate, or your runway to within a reasonable range, partners lose confidence in your operational grip on the business.

Category 5: Competition

46. Who are your competitors? 47. Why haven't the big players in this space done what you are doing? 48. What happens if Google/Amazon/Reliance builds this? 49. How are you different from [specific competitor]? 50. What does [competitor] do better than you? 51. Why hasn't [competitor] entered your specific niche? 52. Have you talked to customers who chose a competitor over you? What did they say? 53. What is your unfair advantage? 54. What would it take for a competitor to replicate what you have built? 55. If a well-funded team started building this tomorrow, how long before they caught up to you?

What partners are probing: competitive awareness and honest self-assessment. Founders who say they have no competition or who cannot acknowledge what competitors do well signal either poor research or defensiveness. Both are red flags.

Category 6: The Founding Team

56. Why are you the right people to build this? 57. How did you meet your cofounder? 58. How do you divide responsibilities? 59. Have you two ever had a serious disagreement? What happened? 60. What does your cofounder do better than you? 61. What do you do better than your cofounder? 62. If your cofounder left tomorrow, would you keep building this? 63. Why are you working on this and not something else? 64. What is your personal connection to this problem? 65. What did you do before this? 66. What is your cofounder's background? 67. Have you worked together before this company? 68. How do you make decisions when you disagree? 69. What is the hardest thing about working with your cofounder? 70. Why this problem, why now, why you?

What partners are probing: team cohesion, founder-problem fit, and the stability of the cofounder relationship. Both founders should be able to answer questions about each other without hesitation.

Category 7: Growth and Strategy

71. How do you plan to grow from here? 72. What is your distribution strategy? 73. How did you acquire your last 10 customers? 74. What is the one metric you are most focused on right now? 75. What is your 12-month plan? 76. What would you do with $500K? 77. What would make the next 3 months a success? 78. What is the biggest risk to your company right now? 79. What keeps you up at night? 80. What would have to be true for this to be a $100M company? 81. When will you raise your Series A and at what metrics? 82. What is the most important thing you need to figure out in the next 6 months? 83. If you could only focus on one thing for the next 90 days, what would it be? 84. What is the hardest part of building this company? 85. What have you tried that has not worked?

What partners are probing: strategic clarity and self-awareness about constraints. Founders who can name their biggest risk and describe what they are doing about it demonstrate operational maturity.

Category 8: YC-Specific Questions

86. Why are you applying to YC? 87. What do you specifically want from YC? 88. Which YC partners do you want to work with and why? 89. What would make YC's investment in you a success? 90. Have you applied to YC before? What changed since then? 91. Are you talking to other investors? 92. Have you received any term sheets? 93. If we funded you, what would you do differently starting Monday? 94. What is the one thing you want us to know about your company that is not in your application? 95. Is there anything in your application that you would change if you could?

What partners are probing: your self-awareness, your preparation, and whether you have a specific and realistic picture of what YC provides. Generic "mentorship and network" answers to "why YC?" reveal a founder who has not thought carefully about what the program actually does.

Category 9: Hard Questions and Stress Tests

96. What is the thing most likely to kill your company? 97. What do your users complain about most? 98. Why haven't you grown faster? 99. What mistake have you made that you regret? 100. If this doesn't work, why won't it work?

What partners are probing: intellectual honesty and resilience. Founders who cannot answer these questions honestly — who deflect, minimize, or become defensive — signal a lack of self-awareness that is one of the most common characteristics of founders whose companies fail. The right answers are direct, honest, and followed immediately by what you are doing about it.

The 10 Questions Every Founder Must Have Perfect Answers For

Based on frequency of appearance across partner accounts and rejected founder interviews, these 10 appear in almost every YC interview:

1. What does your company do? (in one sentence) 2. How many customers do you have and what is your MRR? 3. What is your retention rate? 4. How did you get your first customer? 5. Who are your competitors and why are you different? 6. Why are you the right people to build this? 7. Why hasn't this been solved before? 8. What is the biggest risk to your company? 9. What would you do with $500K? 10. Why are you applying to YC specifically?

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FAQ

Frequently asked questions

What are the most common YC interview questions?
The most frequently reported YC interview questions across founder accounts are: "What does your company do?" (in one sentence), "How many customers do you have and what is your MRR?", "What is your retention rate?", "Who are your competitors and why are you different?", and "Why are you the right people to build this?" These five questions appear in almost every YC interview regardless of sector or stage. Know the answers to all five cold — without hesitation, without hedging, and with specific numbers.
How many questions do YC partners ask in a 10-minute interview?
Typically 8-15 questions in 10 minutes, depending on the pace of the interview and how long your answers run. Fast, concise answers invite more questions — which gives partners more signal. Long, elaborate answers to early questions mean fewer total questions and less opportunity to demonstrate depth across categories. The founders who perform best in YC interviews answer each question in under 45 seconds and leave space for follow-up.
Do YC interview questions vary by sector or stage?
The core categories — what you build, traction, competition, team, and strategy — appear across every sector. The specific questions within each category vary based on your application: partners will ask follow-up questions on anything in your application that raised a question during their review. A B2B SaaS application will get deeper questions on churn, CAC, and sales cycle. A consumer app will get deeper questions on retention and monetization. A pre-revenue application will get deeper questions on user evidence and founder-problem fit.
Should you prepare scripted answers for YC interview questions?
No. Scripted answers produce robotic delivery that partners immediately recognize. Prepare by knowing your numbers cold, practicing each category of question with a live conversation partner until your answers flow naturally, and ensuring both cofounders can answer questions about each other without hesitation. The goal is not memorization — it is such deep familiarity with your own company that any question about it produces an immediate, specific, confident answer.
What happens if you don't know the answer to a YC interview question?
Say so directly. "I don't have that number with me" or "I haven't measured that yet — here's why and here's what I track instead" is more credible than a fabricated or hedged answer. Partners are not testing your ability to answer every possible question — they are testing your honesty and your grip on what matters. A founder who says "I don't know, but here's what I do know" and pivots to a strong related answer demonstrates intellectual honesty. A founder who bluffs through an answer and gets caught demonstrates something much worse.
How do YC partners decide which questions to ask?
Partners read your application in the 30-60 minutes before your interview and identify the questions your application raises but does not answer. Every vague claim ("we have strong traction"), every unclear number, every unexplained decision in your application becomes a potential interview question. The clearest and most specific your application is, the more partners can focus interview time on substantive forward-looking questions rather than clarifying basic facts.
How should both cofounders divide the YC interview questions?
Both cofounders should answer questions naturally — do not pre-divide who answers what. The most common mistake is one cofounder answering 90% of questions while the other sits quietly. Partners notice and interpret it as either a non-contributing cofounder or a team that has not aligned on their narrative. Practice the interview together until both cofounders can answer any question confidently. When one is answering, the other should nod, add specific detail if relevant, and not interrupt or correct.
What YC interview questions are most likely to trip up first-time founders?
Four questions consistently trip up first-time founders: "What is your gross margin?" (many do not know it), "What would happen if you doubled your price?" (reveals pricing confidence), "What does your worst customer look like?" (reveals product-market fit clarity), and "Why hasn't this been solved before?" (often reveals either shallow competitive research or an insight that is thinner than the founder believes). Prepare specific, honest answers to all four before your interview.
How do YC partners react if founders disagree on an answer during the interview?
Minor differences in emphasis are fine and even positive — they suggest authentic answers rather than rehearsed ones. Direct contradictions between cofounders on factual questions (different MRR numbers, different customer counts, different descriptions of the product) are significant red flags. They signal misalignment on what the company actually is. Partners have been known to ask the same question to each cofounder separately to see if the answers match. Know your numbers together. Practice describing the company together until the answers are consistent without being identical.
What is the single best way to prepare for a YC interview?
Run live mock interviews with someone who will ask hard follow-up questions, not softball versions of the questions on this list. Find a YC alumni, a former founder, or a smart friend who knows nothing about your company and ask them to interview you for 15 minutes with no preparation on their end. Real follow-up questions — the ones that come from a genuinely curious, slightly skeptical interviewer — are more valuable preparation than any amount of solo answer rehearsal. Do at least 3 mock interviews before your actual interview. Record them. Watch what breaks down.
Are the questions on this list the same every batch?
The categories are consistent across batches. The specific questions within each category shift slightly based on current YC priorities, the sector you are in, and what your application specifically raises. The 10 questions listed as "must have perfect answers for" have appeared consistently across multiple years of founder accounts and are the most reliable preparation target. The full list of 100 covers the full range of what has been reported — but your specific interview will be shaped by your specific application and your specific company.
How do YC interview questions differ for AI startups in 2025?
AI startups in 2025 face additional probing in two areas: differentiation from foundational model capabilities (why can't GPT-4o do what you do?) and data moat (what data do you have or generate that competitors cannot easily replicate?). Partners are also more likely to ask AI founders about their specific model architecture choices, their evaluation methodology, and their position on the commoditization risk of AI capabilities. Be prepared to explain your technical differentiation in plain language and to describe your data position specifically.
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