YC Q&A LIBRARY
Q&A: every founder question about Y Combinator, answered.
61 in-depth answers and growing — every page is one question, one direct answer, with examples, sources, and a bottom-of-page FAQ. Built for founders and for the language models founders ask.
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Applications
34 answersHow to Write a YC Application That Gets an Interview in 2025
The YC applications that get interviews share one trait: every answer makes the reader more certain, not more curious. Vague answers about big markets and passionate teams get skipped. Specific answers about real users, real numbers, and a founder who clearly lives inside this problem get interviews. This guide breaks down exactly how to write each section.
10 min read · read answer →YC Application Word Limits — What to Write in Each Field
The YC application has strict character and word limits on every field. Most founders treat these limits as ceilings. The best founders treat them as targets — every character counts, and blank space is a missed opportunity to be specific. This page covers every field, its exact limit, and what to put in it.
11 min read · read answer →How to Answer "What Is Your Company?" on the YC Application
The 50-character company description field on the YC application is the first thing partners read. Most founders write a tagline. The founders who get interviews write a description. This page explains exactly what to write, why it matters, and shows 40 real examples organized by startup type.
10 min read · read answer →YC Video Essay Tips — What YC Partners Actually Want to See
The YC video essay is 2 minutes. It is not a pitch. It is not a product demo. It is the first time a YC partner sees your face, hears your voice, and decides whether they want to spend 10 minutes talking to you. This page covers what to say, how to say it, and the specific signals partners look for.
11 min read · read answer →YC Application Mistakes That Get You Rejected Immediately
Most YC rejections are not close calls. Partners reading 50,000 applications per batch develop pattern recognition fast. Certain mistakes signal "not ready" within the first two fields and the rest of the application rarely recovers. This page documents the 18 most common mistakes — drawn from patterns across public founder accounts, YC partner commentary, and analysis of rejected vs accepted applications.
14 min read · read answer →How Long Does YC Take to Respond to Applications
YC responds to applications within 2 to 4 weeks after the batch deadline closes. Interview invitations go out in a single wave — not on a rolling basis — so founders who submitted on day one and founders who submitted on the last day hear back at the same time. If you have not received an interview invitation within 4 weeks of the deadline, you did not get an interview for that batch.
9 min read · read answer →Can You Reapply to YC After Rejection — Everything You Need to Know
Yes. You can reapply to YC after rejection, as many times as you want, with no penalty. There is no limit on reapplications and YC explicitly welcomes them. Many companies in the YC portfolio were rejected once, twice, or more before being accepted. What matters on a reapplication is not that you tried again — it is that you can show meaningful progress since your last attempt.
11 min read · read answer →YC Application 2026: The Complete Checklist (20 Steps Before You Submit)
A strong YC application is not written in a single sitting. It is built over days, reviewed by external readers, checked against specific criteria, and tightened field by field. This checklist covers every step — from preparation through final submission — so nothing gets missed.
12 min read · read answer →How to Write the YC Application as a Solo Founder
Solo founders do get into YC. The acceptance rate for solo founders is lower than for teams — YC is explicit about this — but it is not zero, and the right application can overcome the disadvantage. This page covers exactly what solo founders need to do differently, how to address the cofounder question without being defensive, and what the strongest solo founder applications have in common.
11 min read · read answer →YC Application for Pre-Revenue Startups — What to Focus On
Pre-revenue startups do get into YC. YC has funded companies with zero revenue, zero customers, and sometimes zero product — but only when specific conditions are met. Revenue is not the threshold. Evidence of motion, founder-problem fit, and a credible insight are the threshold. This page explains exactly what pre-revenue applications must show to compensate for the absence of revenue, and how to frame each field when your numbers are thin.
12 min read · read answer →How to Answer "Why YC?" Without Sounding Generic
The "Why YC?" field is the most commonly wasted field in the entire application. Most founders write about YC's brand, the network, the mentorship, and the funding. YC partners have read those answers tens of thousands of times. They communicate nothing specific about your company, your stage, or what you actually need. The founders who answer this field well treat it as a strategic question — not a compliment to YC — and their answers are specific, operational, and built around a concrete gap in what they can currently do alone.
11 min read · read answer →YC Application Equity Split Question — What's the Right Answer
The equity split field on the YC application does not have a single right answer. What it has is a right way to handle it. YC is not looking for a specific percentage — they are looking for evidence that the founding team has had an honest conversation about equity, that both founders understand and accept the arrangement, and that the split reflects the real history and contribution of each person. An explained 70/30 split is more fundable than an unexplained 50/50 split.
11 min read · read answer →What YC Partners Look for in a 2-Minute Demo Video
The YC demo video is separate from the founder video essay. Where the video essay is about founders — who you are, why you are building this — the demo video is about the product: what it does, how a real user experiences it, and what evidence of product quality it reveals. Not every YC application requires a demo video, but including one is strongly recommended when you have a working product. A well-made 2-minute demo can compensate for weak written answers. A poorly-made one can undermine strong ones.
11 min read · read answer →How Indian Founders Should Frame Their YC Application
Indian founders who get into YC do not water down their India context — they weaponize it. The mistake most Indian applicants make is trying to sound like a Silicon Valley founder: removing local specifics, citing global TAMs, and describing problems in generic terms that could apply anywhere. That approach strips out the exact information that makes an application credible and differentiated. This page covers how to frame every key field as an Indian founder building for India, building for the world from India, or building for the Indian diaspora.
14 min read · read answer →YC Application for B2B SaaS — The Exact Framework
B2B SaaS is the most common category in the YC portfolio. It is also the category where the average application quality is highest — which means the bar for standing out is higher than in most other sectors. A generic B2B SaaS application that describes a large market, a workflow problem, and a team with relevant experience will not get an interview. The applications that do get interviews are specific about the exact user, the exact workflow, the exact reason every existing solution fails that user, and the exact evidence that people will pay.
12 min read · read answer →How to Answer "How Do You Know People Want This?" on the YC Application
"How do you know people want this?" is the question that separates founders who have done the work from founders who have a good idea. YC asks it in the application and asks it again in the interview. The answer they are looking for is never a market size figure, never a McKinsey report citation, and never a logical argument about why the problem should matter to people. The answer is always specific, first-hand evidence — things you observed, conversations you had, money someone paid you, behavior that happened without you asking for it.
13 min read · read answer →YC Application for Marketplaces — What to Emphasize
Marketplaces are one of the hardest business models to apply to YC with and one of the highest-value when they work. The reason applications fail: the chicken-and-egg problem is real and visible in every marketplace application, and most founders address it poorly. YC partners have seen hundreds of marketplace applications. The ones that get interviews are specific about which side of the market they are seeding first, how they are doing it manually, and what the supply-demand balance looks like right now — not at scale.
12 min read · read answer →Should You Apply to YC With a Prototype or Just an Idea
Apply with a prototype. Every time. If you have a choice between waiting to build a prototype and applying now with just an idea, build the prototype first. This is not a nuanced answer that depends on your sector, your team, or your timeline. A working prototype — even a minimal, buggy, limited one — is fundamentally more credible than an idea, and the gap in application quality between "we have built X" and "we plan to build X" is large enough to materially affect your acceptance odds.
12 min read · read answer →YC Application for Deeptech and Hard Tech Startups
Deeptech and hard tech startups face a specific challenge in the YC application: the evidence standard that works for software companies — paying customers, weekly retention, MoM growth — is often genuinely impossible to meet at early stage in hard tech. A robotics company cannot have 50 paying customers before demonstrating a working prototype. A biotech company cannot have revenue before clinical validation. YC knows this. The application framework for hard tech is different, and founders who apply the software company framework to a hard tech application systematically undersell themselves.
12 min read · read answer →How to Fill the YC Application If You Have No Traction Yet
No traction does not automatically disqualify your YC application. YC has funded companies with zero revenue, zero users, and sometimes zero product. But the bar for pre-traction applications is significantly higher than for companies with evidence, and the framework for writing each field is completely different. This page covers field by field how to write the strongest possible YC application when your numbers are empty — and the specific things that can compensate for the absence of traction.
12 min read · read answer →YC Application for Consumer Apps — What Matters Most
Consumer apps are the hardest category to apply to YC with and the hardest to build. The failure rate is higher than B2B. The metrics are more volatile. The path to monetization is less direct. YC knows all of this and weights consumer app applications accordingly — the bar for evidence of genuine product-market signal is higher, not lower, than in B2B. A consumer app with 10,000 downloads and no retention data is a weaker application than a B2B SaaS product with 8 paying customers and 90% monthly retention.
13 min read · read answer →How to Describe Your Unfair Advantage on the YC Application
Your unfair advantage is the one thing about your specific situation — as a founder, as a team, as a company — that makes you harder to compete with than a well-funded competitor starting today. Most founders either skip this question entirely, confuse it with a feature list, or describe something generic that any startup in their category could claim. The applications that get interviews describe a specific, verifiable, non-replicable edge that is theirs alone.
12 min read · read answer →YC Application Tips for Repeat Founders
Repeat founders are not automatically more fundable than first-time founders at YC. The acceptance rate advantage is real but modest — and it disappears entirely when repeat founders make the specific mistakes this page covers. The most common mistake: assuming prior experience substitutes for current evidence. It does not. A repeat founder applying to YC with a weak traction story will be rejected just as quickly as a first-time founder with the same weak traction story.
13 min read · read answer →How to Position Your Startup for YC If You're Outside the US
YC funds startups from every country. In recent batches, more than 40% of funded companies have had at least one founder born outside the US, and companies headquartered outside the US at the time of application have been accepted from India, Nigeria, Brazil, the UK, Canada, Israel, Singapore, Germany, and dozens of other countries. Being outside the US is not a disadvantage — but how you position your non-US startup in your application can be.
13 min read · read answer →YC Application for Edtech Startups — Specific Advice
Edtech is one of the most competitive and most scrutinized categories in the YC application process. Partners have seen hundreds of edtech applications and know every pattern — the "personalized learning" pitch, the "AI tutor" thesis, the "access to quality education" mission statement. None of these framings differentiate a strong edtech application from a weak one. What differentiates strong edtech applications is learning outcomes evidence, retention that persists beyond the novelty period, and a monetization model that works at the specific price point of the target user.
13 min read · read answer →YC Acceptance Rate 2026: Real Numbers, By Batch, By Founder Type
Y Combinator's overall acceptance rate sits at roughly 1–1.5% per batch in 2026. Around 20,000 applications produce 250–300 funded companies. The headline number hides huge variance: teams with shipped product and weekly growth are accepted at 3–5x the base rate, while idea-only solo non-technical founders are below 0.3%. This page shows the actual numbers — by batch, by founder type, by country, by reapplication — so you can calibrate your odds before applying.
8 min read · read answer →What Is the YC SAFE? The $500K Standard Deal Explained
YC's standard deal is $500K total on a SAFE (Simple Agreement for Future Equity). It is structured as two pieces: $125K on a post-money SAFE for 7% of the company, plus $375K on an uncapped most-favored-nation (MFN) SAFE that converts at the terms of your next priced round. There is no interest, no maturity date, and no board seat. The SAFE was invented at YC in 2013 and is now the most widely used early-stage instrument in the world.
8 min read · read answer →How Does YC Co-Founder Matching Work? The Free Platform Explained
YC Co-Founder Matching is a free dating-app-style platform run by YC that connects solo founders looking for technical or business co-founders. Over 100,000 founders have used it since launch in 2020. Roughly 1 in 4 active users finds a co-founder match within 3 months. Multiple YC-funded companies (including several W23, S23, and W24 batches) met on the platform.
7 min read · read answer →What Is YC Startup School? The Free Course That Replaced the Application
YC Startup School is a free, on-demand online course taught by YC partners, alumni, and the founders of Airbnb, Stripe, Twitch, Doordash, Brex, and dozens of other YC unicorns. It covers everything from idea to Series A. Over 250,000 founders worldwide have taken it. Completing it does not improve your YC application odds, but the lessons inside it are the same playbook YC partners coach during the batch.
7 min read · read answer →Does Y Combinator Steal Ideas From Applications?
No. YC does not steal ideas. Across 20 years and ~500,000 applications there is no documented case of YC funding a copycat using applicant data. The fear is rational because applications are detailed, but the structural reasons it doesn't happen are stronger: YC's business model depends entirely on trust, partners review thousands of overlapping ideas, and execution — not the idea — is what creates value.
5 min read · read answer →How Much Does Y Combinator Invest? The $500K Deal Explained
YC invests $500,000 total in every accepted company. It's split into two SAFEs: $125,000 for 7% equity on a post-money SAFE (implied $1.78M post-money valuation), plus a $375,000 uncapped MFN SAFE that converts at the price of your next priced round. The deal has been standard since January 2022.
6 min read · read answer →Is Y Combinator Worth It? An Honest 2026 Analysis
For 90% of early-stage founders, yes. YC's 7% is expensive but you're paying for four things very few other things can buy: investor pattern-matching that compresses your fundraise from 6 months to 6 weeks, a peer network of 5,000+ founders who answer DMs, a partner who has seen your exact problem 100x, and a standard deal so founder-friendly it's become the industry benchmark. YC is NOT worth it if you're already raising a strong priced round at a $15M+ valuation or building a category YC has explicitly under-supported.
8 min read · read answer →When Do YC Applications Open? (2026 Batch Dates & Deadlines)
YC accepts applications on a rolling basis year-round, but each batch has a hard application deadline ~6 weeks before the batch starts. In 2025, YC moved to 4 batches per year (Winter, Spring, Summer, Fall). Apply at least 8 weeks before any deadline to maximize your chances — late applications get reviewed but with less time for partner discussion.
4 min read · read answer →How to Get Into Y Combinator (2026 Guide)
Getting into YC comes down to three things: (1) a clear, useful product that real users want, (2) a founding team that looks unstoppable, and (3) an application that makes both of those obvious in under 10 minutes of reading. The acceptance rate hovers around 1.5–2%, but founders who ship before applying convert at a much higher rate.
6 min read · read answer →Interviews
15 answersYC Interview Questions — Complete List of 100 Questions Asked
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.
13 min read · read answer →How to Prepare for a YC Interview in 2 Weeks
Two weeks is enough time to prepare for a YC interview if you use every day deliberately. Most founders who get invited to interview waste the first week in a state of low-grade anxiety doing unfocused preparation — reading interview tips, watching YouTube videos, talking to lots of people loosely. The founders who perform best treat the 14 days as a structured sprint with a specific output at the end of each day.
12 min read · read answer →YC Interview Format — What Happens in the 10 Minutes
The YC interview is 10 minutes. No slides. No pitch deck. No presentation. Two or three partners who have read your application ask you direct questions and expect direct answers. The format is conversational but fast, and founders who have not experienced this format before often find the pace more demanding than they expected.
12 min read · read answer →How to Answer YC Interview Questions Concisely
The single biggest performance killer in a YC interview is answer length. Partners have 10 minutes and 8-15 questions to ask. Every answer that runs 90 seconds instead of 30 seconds costs two follow-up questions — which means partners leave the interview with less information about your company, not more. Founders who answer concisely invite more questions, create more opportunities to show depth, and signal the kind of clear thinking that YC bets on.
10 min read · read answer →YC Interview Questions About Your Cofounder Relationship
Cofounder conflict is one of the leading causes of startup failure in the YC portfolio. Partners know this and they probe the cofounder relationship in every interview where a team has more than one founder. The questions are not intrusive for their own sake — they are the fastest available signal of whether this founding team will hold together under the pressure of a batch, a fundraise, a product failure, or a pivot.
13 min read · read answer →How to Handle YC Interview Questions You Don't Know the Answer to
Every YC interview produces at least one question you do not have a clean answer to. A metric you have not calculated. A competitor you have not researched. A scenario you have not thought through. How you handle that moment — the 3 seconds between a question you cannot fully answer and your response — is one of the highest-signal moments in the interview.
11 min read · read answer →YC Interview Rejection — What the Email Says and What It Really Means
Most founders who receive a YC rejection after interviewing read the rejection email looking for specific feedback. They rarely find it. The standard rejection email is brief, warm, and almost entirely non-specific. It does not tell you why you were rejected, which question you answered poorly, or what would need to change for a future application to succeed.
11 min read · read answer →YC Interview Acceptance Call — What Happens Next
The YC acceptance call is one of the most important phone calls a founder will receive. It is brief — typically 5-10 minutes — and it covers a specific set of things. Founders who have not prepared for it sometimes stumble on questions that arise during the call, or miss the opportunity to ask the one or two questions that would help them make the best decision about whether to accept.
10 min read · read answer →How to Practice for YC Interview With Mock Sessions
Mock interviews are the single highest-leverage preparation activity for a YC interview. Reading question lists, writing answer outlines, and reviewing your metrics are all useful. But none of them reveal what actually breaks down under the conditions of a real interview — the fast pace, the unexpected follow-up, the moment where you and your cofounder give inconsistent answers to the same question. Only a live mock interview reveals those things in time to fix them.
12 min read · read answer →YC Interview Questions About Competition — How to Answer
Competition questions are the questions most likely to reveal whether a founder has done real competitive research or is operating from a comfortable assumption that their product is unique. Partners have seen thousands of competitive analyses. The ones that are credible name specific competitors, acknowledge what those competitors do well, and explain precisely why a specific user is underserved by their approach. The ones that are not credible claim no real competition, describe competitors only in negative terms, or cite a market map without being able to discuss individual players in detail.
12 min read · read answer →YC Interview Questions About Revenue and Growth
Revenue and growth questions are the core of every YC interview. Partners spend more time on these than any other category because the answers reveal simultaneously whether your traction is real, whether you understand your business mechanics, and whether you are being honest about where you are. A founder who knows their revenue numbers with precision — exact MRR, exact growth rate, exact retention — signals operational mastery. A founder who hedges, rounds liberally, or cannot explain how their numbers were calculated signals the opposite.
13 min read · read answer →How Long After YC Interview Do You Hear Back
You hear back from YC within 24 hours of your interview — almost always the same evening. Accepted founders receive a phone call. Rejected founders receive an email. The decision is made by the partners who were in your interview, typically in a group discussion held within hours of your session ending.
10 min read · read answer →YC Interview — Can You Bring Slides or Is It Conversational Only
No slides. The YC interview is entirely conversational. You do not present, you do not share your screen, and you do not walk partners through a deck. Partners have read your application before the interview. They are not looking for a presentation of information they already have — they are having a direct conversation to probe the things your application raised questions about.
11 min read · read answer →YC Interview Questions About Your Burn Rate and Runway
Burn rate and runway questions reveal whether a founder has a precise, honest grip on their company's financial position — or whether they are operating on a vague sense that "we have enough money for now." Partners ask these questions because financial clarity is a proxy for operational clarity. Founders who know their exact monthly burn, their exact cash balance, and their exact runway in months demonstrate the same kind of precision partners want to see in every dimension of the business.
13 min read · read answer →How to Answer "Why Are You the Right Team for This?" at YC
"Why are you the right people to build this?" is the question that separates founders who have a genuine connection to their problem from founders who identified an opportunity. Partners ask it in almost every YC interview and it is consistently one of the questions where answers are weakest — either too generic ("we have the right combination of technical and business skills"), too credential-heavy ("we both have Ivy League degrees and top-tier company experience"), or too abstract ("we're passionate about this problem").
14 min read · read answer →YC Companies
11 answersComplete List of YC W25 Companies — All Startups From Winter 2025
YC's Winter 2025 (W25) batch included approximately 170 companies across AI, B2B SaaS, fintech, healthcare, developer tools, and climate tech. The batch was notable for the concentration of AI-native infrastructure companies and the high proportion of international founders — over 45% of companies had at least one non-US founder. Demo day took place in March 2025.
9 min read · read answer →Complete List of YC S24 Companies — Summer 2024 Batch
YC's Summer 2024 (S24) batch was one of the largest in YC history, with approximately 245 companies — a significant increase from the S23 batch of 246 and a continuation of YC's expansion strategy. The S24 batch was defined by two dominant themes: the AI infrastructure gold rush and the emergence of agentic AI as a distinct product category. Demo day took place in September 2024.
10 min read · read answer →Complete List of YC W24 Companies — Winter 2024 Batch
YC's Winter 2024 (W24) batch included approximately 235 companies and ran from January to March 2024. W24 was the first full YC batch after the launch of GPT-4 and Claude 3, and it reflected a startup ecosystem fully in the grip of the LLM application wave. Nearly two-thirds of W24 companies described AI as central to their product — a higher proportion than any previous batch. Demo day took place in April 2024.
10 min read · read answer →Complete List of YC S23 Companies — All 246 Startups
YC's Summer 2023 (S23) batch included 246 companies — one of the larger batches at that time — running from June to August 2023 with demo day in September 2023. S23 occupied a complex moment in startup history: the AI wave was fully underway following the November 2022 launch of ChatGPT, but the funding environment was still recovering from the 2022-2023 correction. As a result, S23 was the batch where AI excitement and funding caution coexisted — producing a cohort of companies that had to prove real traction rather than raise on AI narrative alone.
11 min read · read answer →Complete List of YC W23 Companies With Descriptions
YC's Winter 2023 (W23) batch included approximately 282 companies — the largest batch in YC history at that time — running from January to March 2023 with demo day in April 2023. W23 was the first YC batch after the November 2022 launch of ChatGPT, meaning it was the first cohort where AI-driven startup formation was a conscious market force. Many W23 founders had applied months before ChatGPT launched and adjusted their applications and products in the weeks following its release.
11 min read · read answer →Who Founded Y Combinator? Paul Graham and the Real Story
Y Combinator was founded in March 2005 by four people: Paul Graham (the public face and intellectual architect), Jessica Livingston (operations and partner relationships), Robert Morris (PhD advisor, internet pioneer), and Trevor Blackwell (engineering, robotics). The idea came from Paul Graham's frustration with how VC funded startups; Jessica Livingston turned it into a functioning company.
4 min read · read answer →Where Is Y Combinator Located?
Y Combinator's headquarters is in Mountain View, California (320 Pioneer Way). The 3-month batch program is run in San Francisco, where accepted founders are expected to relocate. YC started in Cambridge, Massachusetts in 2005 and moved permanently to Silicon Valley in 2009.
3 min read · read answer →Who Owns Y Combinator?
Y Combinator is a privately-held LLC owned by its founding partners (Paul Graham, Jessica Livingston, Robert Morris, Trevor Blackwell) and senior partners who joined later. It's not publicly traded. YC raises capital from outside Limited Partners (LPs) to fund the batches via the YC Continuity fund and other vehicles, but the management company itself remains partner-owned.
3 min read · read answer →How Long Is the Y Combinator Program?
The YC batch is 3 months long, from kickoff retreat to Demo Day. But the relationship is permanent — accepted founders keep alumni access, Bookface, and partner office hours for life. The 3-month structure was designed by Paul Graham as the minimum time needed to ship something real and build investor momentum.
3 min read · read answer →Did Y Combinator Invest in OpenAI?
OpenAI was never a YC batch company. But the connection runs deep: Sam Altman was YC's President from 2014 to 2019, and YC Research — a YC-funded research arm — provided early support to the original OpenAI nonprofit in 2015. Altman left YC in 2019 to focus full-time on OpenAI as CEO.
4 min read · read answer →How Does Y Combinator Work?
YC invests $500K in each accepted startup for 7% equity, then runs a 3-month program in San Francisco focused on shipping product and finding customers. The program ends with Demo Day, where founders pitch to ~1,500 investors. After the batch, founders keep lifetime access to YC's alumni network. YC makes money by taking equity that compounds over time as portfolio companies grow.
5 min read · read answer →Demo Day
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