20 years of Y Combinator, distilled for founders.
Every YC essay, every Request for Startups, every founder interview, every public S-1 — read, organised and turned into clear playbooks. The open library we wish existed when we started. Free to read. Free to download. Every source linked.
/for aspiring founders
Everything an aspiring founder needs, in one place.
Y Combinator has shaped the modern startup playbook — we've spent 1,000+ hours organising their publicly available wisdom into clear, free guides. From writing your application to picking the right idea to running your first user interviews. All free. All sourced.
01 · Apply
How to apply to Y Combinator (2026)
Every question on the YC application, what the partners are listening for, and side-by-side strong vs weak answers — all built from public YC partner talks and accepted application teardowns.
Read the application guide →02 · Interview
The YC interview, decoded
What the 10-minute YC partner interview actually covers, the question patterns to expect, and how to practice — distilled from 50+ public founder recaps.
Prep for the interview →03 · Ideas
15 YC startup ideas for 2026
Every category in YC's 2026 Request for Startups, expanded into a complete founder playbook — customer, wedge, 8-week MVP, pricing, and the first 10 customers.
Browse the 15 ideas →04 · Essays
20 years of YC essays, distilled
pg, Jessica, Sam, Geoff, Garry — every essential YC essay distilled to the argument, the evidence, and what changed since publication. Always linked back to the original.
Read the essays →05 · Frameworks
The YC mental models
Default Alive vs Default Dead, Do Things That Don't Scale, Make Something People Want — the operating models YC partners use, with worked examples you can apply this week.
Open the frameworks →06 · Free PDFs
Free founder resources · No email
Application cheatsheet, interview prep, the Default Alive calculator, user interview script, PG quote pack — every PDF is free to download. No gate, no upsell.
Grab the PDFs →Every guide is built from publicly available Y Combinator material — essays, partner talks, founder interviews, public S-1 filings. Sources are linked on every page.
/database-categories
Nine angles on the YC ecosystem, organised for founders.
The 45 databases below are grouped by what you're trying to learn. Click any group to jump straight to the cards that matter for your stage.
Playbooks
8Step-by-step founder playbooks for the categories YC wants funded next — customer, wedge, MVP path, pricing.
view databases →Core Databases
7The foundational YC datasets — pivots, graveyards, first 1000 customers, idea evolution, founder origins.
view databases →Batch Packs
3Every YC batch, fully decoded — companies, founders, traction signals, pivots already happening.
view databases →Vertical Packs
7Per-industry views of the YC portfolio — AI, fintech, SaaS, consumer, healthtech, edtech, India.
view databases →Deep Reports
9Long-form analyses — unicorns, dead unicorns, acqui-hires, IPOs, fundraising mechanics, solo founders.
view databases →Founder Files
4The non-business stories every founder eventually meets — burnout, co-founder splits, relationships, almost-quit moments.
view databases →Annual Reports
3Year-end views YC doesn't publish — success rates, failure patterns, emerging categories, the portfolio to watch.
view databases →Master Playbooks
3Combined growth, fundraising and survival playbooks — the full arc from idea to first million in revenue.
view databases →Subscription
1Monthly YC intelligence — five deep dives, one database update, one trend report, every month.
view databases →45
Total databases
20yr
Of YC history
100%
Publicly sourced
$0
To start reading
/the-database
The full YC library. 45 databases · 4 live · 41 shipping soon.
Pivots, first-1000-customer stories, batch packs, vertical packs, founder origin files — every angle of the YC ecosystem, structured and sourced. Each database has its own page, its own sources, and its own FAQ.
Launch Like a YC Founder — Product Hunt Playbook
Playbooks
The Product Hunt playbook for early-stage startups, calibrated to the 2026 algorithm.
RFS Playbook 2026
Playbooks
15 YC RFS categories. 15 complete founder playbooks.
Rejection Database
Core Databases
YC alumni who got rejected, pivoted, or nearly died — and built generational outcomes.
YC Solo Founder Database
Core Databases
20+ verified YC solo founders. Every case study. One bundle.
YC Master Pivot Database
Core Databases
500+ YC Companies. One Pivot. One Spreadsheet.
YC Graveyard
Core Databases
300+ YC Companies That Died. Here's Exactly Why.
YC First 1000 Customers Database
Core Databases
How 300+ YC Companies Got Their First 1000 Customers.
YC Idea Evolution Database
Core Databases
What They Applied With vs What They Became.
YC Founder Origin Database
Core Databases
What 500 YC Founders Did 12 Months Before Founding.
YC W25 Batch Intelligence Pack
Batch Packs
Every W25 Company. Every Founder. One Pack.
YC S24 Batch Intelligence Pack
Batch Packs
The S24 Batch. Fully Decoded.
YC W24 Batch Intelligence Pack
Batch Packs
W24 With Full Hindsight.
YC Fintech Founder Pack
Vertical Packs
Every YC Fintech Company. One Pack.
YC AI Founder Pack
Vertical Packs
Every YC AI Company. Pre and Post ChatGPT.
YC SaaS Founder Pack
Vertical Packs
300 YC B2B SaaS Companies. The GTM Playbook.
YC Consumer App Founder Pack
Vertical Packs
150 YC Consumer Apps. Viral, Retention, Monetization.
YC India Founder Pack
Vertical Packs
Every Indian Founder In YC History.
YC Healthtech Founder Pack
Vertical Packs
100 YC Health Companies. FDA, Hospitals, GTM.
YC Edtech Founder Pack
Vertical Packs
YC Edtech: Before, During, and After COVID.
First 1000 Customers — B2B SaaS Edition
Playbooks
50 YC B2B Companies. Week By Week.
First 1000 Customers — Consumer Edition
Playbooks
50 YC Consumer Companies. The Tipping Point.
The PMF Playbook — Fintech Edition
Playbooks
30 YC Fintech Founders. The PMF Metric.
The $0 Marketing Playbook — B2B Edition
Playbooks
40 YC B2B Companies. $1M ARR. Zero Ad Spend.
The $0 Marketing Playbook — Consumer Edition
Playbooks
40 YC Consumer Companies That Went Viral Free.
The Great Pivot — AI Edition
Playbooks
50 Companies That Pivoted Into or Away From AI.
YC Unicorns — The Untold Middle
Deep Reports
20 YC Unicorns. The Series A to $1B Years.
YC Dead Unicorns Autopsy Report
Deep Reports
YC Companies That Hit $500M+ Then Collapsed.
YC Acqui-hire Intelligence Files
Deep Reports
50 YC Companies Acquired For Their Team.
YC IPO Complete Files
Deep Reports
Every YC IPO. Batch Day to Bell.
The Burnout Files
Founder Files
40 Founder Mental Health Stories.
The Co-founder Breakup Files
Founder Files
30 Documented YC Co-founder Splits.
The Almost Quit Files
Founder Files
35 YC Founders On Their Lowest Moment.
The Founder Marriage Files
Founder Files
25 YC Founders On Relationships Under Pressure.
YC Fundraising Intelligence Report
Deep Reports
50 YC Companies. Real Numbers. Real Stories.
State of YC 2024 — Complete Report
Annual Reports
The Annual Report YC Never Publishes.
State of YC 2023 — Complete Report
Annual Reports
2023 With The Hindsight 2024 Provides.
YC India Annual Report 2024
Annual Reports
Built Specifically For Indian Founders.
The Complete YC Growth Playbook
Master Playbooks
First 1000 + PMF + First $1M ARR. One Doc.
The Complete YC Fundraising Playbook
Master Playbooks
Seed to Series A. Real Founder Stories.
The YC Founder Survival Kit
Master Playbooks
Burnout + Co-founder + Runway + Almost Quit.
YC vs Non-YC Outcomes Report
Deep Reports
50 Matched Pairs. The Honest Comparison.
YC Batch vs Batch Analysis 2010–2024
Deep Reports
Which Batches Produced The Most Unicorns. Why.
The YC Solo Founder Complete Report
Deep Reports
Every Solo Founder In YC History.
The YC Second-Time Founder Report
Deep Reports
40 Founders On Their Second Company.
YC Insights Monthly Intelligence
Subscription
5 Deep Dives. 1 Database Update. Every Month.
Every database has its own page with sources, FAQ and download. Tap any card to open it.
From the blog · /blog
Learn YC by what you actually want to know.
Posts are organized by learning track — rejected founders, accepted founders, pivots, the graveyard, first 1000 customers, AI, fintech, solo founders, burnout, co-founder breakups. Every post links back to its source database.
Learn from rejected YC founders
Learn From Rejected YC Founders: What Airbnb, Stripe And Reddit Did The Day After
Every founder in the Rejection Database got told no — by investors, by YC partners, by both. What they did in the next 48 hours is the story.
Analysis · 10 min →
Learn from accepted YC founders
Learn From Accepted YC Founders: What 100+ Successful Applications Have In Common
Patterns from publicly shared accepted YC applications — Stripe, Airbnb, Reddit, DoorDash — and the answers that worked.
Data & Stats · 8 min →
Learn from YC founders who pivoted
Learn From YC Founders Who Pivoted: The 9 Pivots That Built Generational Companies
Twitch was Justin.tv. Brex was VR for Brazil. Instagram (pre-YC era) was Burbn. Here's what triggered the pivot — and the week it actually happened.
Analysis · 11 min →
Learn from YC companies that died
Learn From YC Companies That Died: The Four Causes Of Death
300+ YC companies shut down on the public record. The cause clusters into four patterns — market, product, team, capital — and every one is preventable.
Analysis · 9 min →
Learn how YC founders got their first customers
Learn How YC Founders Got Their First 1000 Customers (By Channel)
Cold email, Reddit, the YC network, one viral tweet — across 300+ YC companies, the channel that worked is shockingly concentrated.
Playbook · 9 min →
Learn from YC AI founders
Learn From YC AI Founders: Who Repositioned In 10 Days When ChatGPT Shipped
November 30, 2022 was a fault line. Some YC AI companies repositioned in two weeks, some never recovered. Here's the split.
Analysis · 10 min →
START BUILDING
20 years of YC, organised for founders.
Every guide and database we publish is free to read on the web and free to download as a PDF. Built from publicly available material. Sources linked on every page. If we ever charge for something, we'll say so plainly.
15
RFS playbooks
60+
Founder profiles
32+
Comeback stories
$0
To get started
An independent resource · Not affiliated with Y Combinator · Every claim has a public source
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