YC ALUMNI DATABASE

List of YC Companies & Alumni, by Batch.

We track 87 YC companies with full founder stories, rejection case studies, or documented pivots. Grouped by batch, newest first. New companies added every week.

What's in here

Every row links to source-verified material — a long-form founder story, a rejection case study, or both. Want the raw data on every YC company ever? See our databases.

Famous YC Companies

The best-known Y Combinator alumni — every one has a full source-linked founder story on YC Insights.

Batch S19

3 companies

Batch W17

1 company

Batch W15

1 company

Batch W14

2 companies

Batch S13

1 company

Batch S12

3 companies

Batch W12

1 company

Batch S11

1 company

Batch W10

1 company

Batch S09

2 companies

Batch W09

1 company

Batch S08

4 companies

Batch W08

9 companies

Trigger.io (originally named "Trigger")

story

Amir Nathoo

Three Cambridge and MIT-educated engineers left corporate jobs at IBM to build the simplest way for web developers to create native mobile apps — got into YC, raised money, grew fast, and then watched the entire HTML5-vs-native debate kill their market before they could outlast it.

Snaptalent

story

Sumon Sadhu

A Oxford-educated biochemist dropped his PhD, got headhunted by Paul Graham into one of the earliest YC batches, built the world's first IP-targeted developer job ad network, made $30K before Demo Day — and then shut it all down two years later because he was five years too early for the market he was trying to create.

RescueTime

story

Tony Wright

While every other startup was chasing hockey-stick metrics, three Seattle founders quietly built a product on evenings and weekends to answer one brutally honest question: "Where does all my time actually go?" — and in doing so, created one of the most enduring productivity tools the internet has ever seen.

Omnisio

story

Ryan Junee

Three Australians with engineering degrees, no prior exits, and no Silicon Valley network walked into YC with a single powerful insight — online video is a static, one-way broadcast when it could be a living, interactive medium — and sold that insight to Google less than a year later.

Kirkland North (product: PlayTurf / Turf)

story

Gabe Smedresman

A Yale student accidentally built a game so addictive that 25% of his entire campus played it — then turned that accident into a YC-backed startup, only to discover that virality and a business are two very different things.

Machine Zone, Inc. (formerly Addmired)

story

Gabriel "Gabe" Leydon

A man who started his company while collecting unemployment benefits — and who came from the dying world of coin-op arcade machines — looked at the iPhone and saw something everyone else missed: not a phone, not a gaming device, but a virtual supermarket in everyone's pocket. He was right, and it made him a billionaire.

Insoshi

story

Michael Hartl

Two Harvard-educated physicists with PhDs built the "WordPress for social networks" in Ruby on Rails, got into YC, became one of GitHub's most-forked repositories, nearly raised a significant funding round — and then watched the 2008 financial crisis kill the deal in October. The company shut down. The founder wrote a tutorial instead. That tutorial made $750,000 and became the most widely read Rails resource in the world.

A Thinking Ape (ATA)

story

Kenshi Arasaki

Three Canadian engineers quit Amazon, got into YC with a chat app, watched it fail to take off — then noticed something unexpected in their own data: people were using their chat rooms to form war clans. They ignored everything they'd built and followed the community. That pivot became one of Canada's most profitable mobile game studios, built entirely without venture capital.

280 North, Inc.

story

Francisco Tolmasky

Three USC college friends — two of whom had built parts of the original iPhone — got so frustrated with how terrible web development was that they secretly built a better version of Apple's own desktop toolkit for the web, launched it as open source, and were acquired by Motorola for $20 million just two years later.

Batch S07

6 companies

Dropbox

story

Drew Houston

Drew Houston couldn't get product/market signal because nobody understood what Dropbox did. So in 2008 he made a screencast aimed at one community — and woke up with 70,000 new users.

Songkick

story

Ian Hogarth

A literature graduate, a Cambridge-trained engineer, and a best friend from university — none of them startup people — solved a problem so personal and obvious that they almost talked themselves out of applying. Songkick became the world's second-largest concert platform by refusing to outsmart itself: they just built what one of them desperately wished existed.

SocialPicks

story

Weiting Liu

A Taiwanese immigrant and Stanford engineer watched Mark Zuckerberg speak and thought, "It's not impossible to build something big right after school" — then spent the next two years trying to do exactly that, turning stock market communities into a social graph before anyone called it fintech.

iJigg (later Top440)

story

Shadab Farooqui

A 25-year-old from Bombay who never planned to be a founder accidentally built one of the internet's first social music platforms, got into YC, scaled to 5 million users — then watched the music industry kill everything he built.

AppJet, Inc. (pivoted to → Etherpad)

story

Aaron Iba

Three ex-Google engineers left stable, prestigious jobs to build a developer platform nobody used — then accidentally invented real-time collaborative editing on a Friday afternoon, watched that side project become the real company, and got acquired by Google two years later. The thing they built to demo the product they failed at became one of the most influential pieces of software infrastructure in the modern internet.

Anywhere.FM

story

Sachin Rekhi

Paul Graham told them he hated their idea — then funded them anyway, on one condition: come up with a new one. What happened next is one of YC's clearest lessons about what actually gets you in: the team, not the idea.

Batch W07

7 companies

Zenter

story

Wayne Crosby

Two PhD engineers — one applying to YC the same night his wife told him she was pregnant — built a browser-based PowerPoint killer in a few months, got acquired by Google, and accidentally created the tool that over a billion people now use to present their ideas to the world.

Weebly

story

David Rusenko

Three college kids built a website builder as a class project, applied to YC with one hour left before the deadline, got told their idea was "the worst ever heard" at their first public demo — and spent the next 12 years quietly proving everyone wrong on the way to a $365 million exit.

Tsumobi

story

Joshua Wilson

Two MIT undergrads on leave of absence got into YC in 2007, raised seed funding from the legendary Ron Conway, and built a technically prescient mobile infrastructure product — one year before the iPhone App Store made their entire approach obsolete overnight.

Octopart

story

Andres Morey

Three physics PhD students were so frustrated searching for electronic components for their lab experiments that they built a search engine for it — dropped out of grad school, nearly went broke during the 2008 financial crisis, refused to quit, and turned a boring niche into a half-million-user platform that got acquired eight years later.

Heysan

story

Gustaf Alstromer

A team of Swedish founders shipped the right product two years too early, built 1 million users without cracking growth, got acquired quietly — and then the CEO spent the next decade becoming one of the world's foremost experts on the exact problem that killed his company: distribution.

Dropbox

story

Drew Houston

A MIT grad forgot his USB drive on a 4-hour bus ride, spent the trip building a solution instead of complaining about the problem — got rejected by YC once, almost didn't apply again, made a bedroom demo video at 3am that went viral, found a co-founder in 2 weeks, and built the company that became the first YC startup ever to go public.

Twitch (then Justin.tv)

case

Justin Kan, Emmett Shear, Michael Seibel, Kyle Vogt

Justin.tv was a YC company that flatlined. They quietly built a 'gaming' subdirectory that ate the whole company.

Batch S06

3 companies

Batch W06

1 company

Batch Summer 2007

7 companies

ZumoDrive (by Zecter, Inc.)

story

David Zhao

Three engineers from Microsoft and Amazon saw the same broken problem every day at their desk jobs — carrying content between devices was painful — and instead of complaining about it, they quit, applied to YC, pivoted once, and built the technology that powered HP's entire netbook line before Dropbox was even a household name.

Splashup (originally named Fauxto, incorporated as Faux Labs, Inc.)

story

Dave Brushinski

Dave Brushinski built the world's first browser-based Photoshop-like editor in 2006 — layers, brushes, effects, the whole thing — before anyone else had proved it was possible. He got into YC, got press, got users. Then the market caught up, better-funded competitors arrived, Flash died, and Splashup quietly closed. The idea was right. Almost everything else was a lesson.

Fuzzwich / Habit Industries

story

Rob Fitzpatrick

Two college friends pitched a video game studio to YC, pivoted the idea mid-interview when the partners tore their business plan apart, got funded anyway, built an animation platform used by Sony and Aardman, raised from top-tier investors — and still shut down. Then Rob Fitzpatrick turned the entire painful experience into The Mom Test, a book that has saved thousands of startups from making the exact mistakes he made.

Disqus

story

Daniel Ha

Two college friends, bored in computer science classes and building side projects for fun, accidentally created the internet's default comment system — not by chasing a big idea, but by following the one small feature that people actually showed up to use.

ContestMachine

story

Savraj Singh

Three Microsoft engineers left their stable jobs, got into YC Summer 2007 alongside Dropbox and Arash Ferdowsi, built a real product that actual beauty bloggers loved — then ignored the most important warning Paul Graham ever gave them, and learned the hard way that being technical is not enough.

Blue Frog Gaming

story

Matt Maroon

A professional poker player from Akron, Ohio walked into Y Combinator with a fantasy sports gambling idea, got funded, watched that idea fail — then accidentally built the largest virtual universe on Facebook by launching a side project to promote a product nobody wanted.

Biographicon

story

Ethan Herdrick

Two programmers with a genuinely interesting idea — "Wikipedia, but for every person on earth, not just famous ones" — got into YC, built the product, launched it publicly, and watched it die in silence five months later. Not because the idea was wrong, but because they launched a community product with nobody in the community.

Batch Winter 2007

3 companies

Batch

1 company

Batch Winter 2008 (one of the earliest cohorts — only 21 companies)

1 company

Batch Summer 2005 — YC's Very First Batch Ever

2 companies

Batch Winter 2006 — one of YC's earliest ever cohorts

1 company

Batch Summer 2006

1 company

Batch Summer 2008

2 companies

Batch Winter 2006 (One of YC's earliest-ever batches)

1 company

Batch Summer 2005 — The Very First YC Batch Ever

1 company

Batch Summer 2006 (YC's 2nd year — one of the earliest batches ever)

1 company

Batch Summer 2005 (Asynchronous investment — did not participate in standard YC cycle)

1 company

Batch Summer 2006 — Inaugural YC Class

1 company

Batch Summer 2005 — The very first YC batch ever funded

1 company

Batch Winter 2006

1 company

Batch Summer 2006 (one of YC's earliest classes)

1 company

Batch Summer 2007 (5th ever YC batch)

1 company

Batch Summer 2005 — YC's very first batch ever

1 company

Batch Winter 2008

7 companies

MightyQuiz

story

Ben Silbermann

A doctor's son from Iowa who was never supposed to be a founder, never learned to code, and watched his first YC company quietly die — then used everything he learned from that failure to build one of the most-used websites on the internet.

Mixwit

story

Radley Marx

Two designers built the most loved online mixtape of 2008, got into YC, grew a passionate user base — and then shut down because they were too honest to pretend the music industry would leave them alone.

Ninite (formerly BaseShield / Secure By Design Inc.)

story

Patrick Swieskowski

Two open-source hackers were so fed up with the ritual humiliation of reinstalling Windows — the toolbar junk, the "click next 47 times" installers, the adware hiding inside free software downloads — that they built the cure. Fifteen years later, it still runs with 2 people and serves NASA.

Joberator

story

Jorge Ortiz

A Stanford-trained engineer looked at the STEM hiring market in 2007, saw a broken connection between brilliant talent and the companies that needed them most, got accepted into YC to fix it — and in doing so, built the skills and credibility that launched a career at three of Silicon Valley's most important companies.

Heroku

story

James Lindenbaum

Three developers at a boring consulting shop in Los Angeles fell in love with Ruby, went to a conference that felt like a religious awakening, and built a product nobody wanted — until they pivoted to what everyone was secretly already using them for. The result: a $212M exit on $13M raised, and a deployment command — `git push heroku main` — that a generation of developers will never forget.

FathomDB

story

Justin Santa Barbara

A Cambridge-educated engineer working odd jobs in London spotted a problem that the entire cloud industry would eventually validate — databases were still being run like it was 1995 — got into YC in 2008, built the world's first relational Database-as-a-Service, and then watched Amazon build the same thing six months later. FathomDB's story is not one of failure — it's one of being exactly right, at exactly the wrong time, against exactly the wrong competitor.

BitSample → Ninite

story

Patrick Swieskowski

Two solo founders walked into YC W08 with two different ideas, met each other, killed both ideas, failed at an app store, and accidentally built one of the most reliable and beloved utility tools on the internet — with a team of just two people, forever.

Batch 2009

1 company

Batch Summer 2005 — YC's very first batch, ever

1 company

Batch Winter 2006 (YC's very second batch ever)

1 company

Batch Winter 2006 — one of YC's earliest cohorts

1 company

Batch Summer 2007 (One of the first 5 YC cohorts — same batch as Disqus)

1 company

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