Listen to a podcast episode where Y Combinator CEO Gary Tan explains why YC tends to outperform many other Silicon Valley startup accelerators.

Y Combinator was founded in 2005 to bridge gaps between founders and investors

In one of Paul Graham’s essays on his website, he took the time to explain how and why he and his cofounders (including his girlfriend at the time, and now wife, Jessica Livingston), came up with the idea of and eventually created Y Combinator.

Y Combinator changed the way startups around the world are built

Many of the philosophies that the leaders of Y Combinator have infused into the program’s portfolio companies have become the playbook for building the next big thing, such as its focus on founder personality and more.

Read Paul Graham’s initial post announcing YC’s first batch

In March 2005, Y Combinator cofounder Paul Graham announced the program that would become Y Combinator on his website.

Y Combinator cofounder Paul Graham keeps a public archive of his insightful essays

In addition to cofounding Y Combinator and other companies before it, Paul Graham is a prolific writer and artist. He chronicled many of his thoughts while building Y Combinator in a series of dozens of candid essays, all of which you can read in an online archive.

Y Combinator, the startup accelerator, gets its name from the 'Y combinator' computer science concept.

YC was partly inspired by an investor named Julian Weber

Y Combinator Cofounder Paul Graham’s former professor’s husband Julian Weber provided $10K in seed funding to Graham’s previous startup, Viaweb in its early days. In exchange, Weber received 10% of the company. Weber’s involvement inspired Graham to start a program where investors were more involved with the companies they contributed seed funding to.

Y Combinator cofounder, Jessica Livingston, once interviewed her husband and cofounder, Paul Graham

Two of Y Combinator's cofounders, Jessica Livingston and Paul Graham, were in a romantic relationship before they started the accelerator. They later married, and much later, Livingston started a podcast. In an episode of her podcast, Livingston and her cohost interview Graham about the beginning of YC and more.

Stanford’s ‘How to Start a Startup’ series

Stanford’s archive of lectures about creating a startup includes advice from Y Combinator notables such as former YC president and OpenAI CEO Sam Altman and YC Cofounder Paul Graham.

Dive deep into the numbers that shape each YC deal

Y Combinator invests $500K into each company in any given batch. $125K of that investment converts into a fixed 7% in ownership of the startup, and the other $375K is invested on something called an uncapped MFN safe. YC explains what that means and more terms of the deal in a detailed article on their website

Visualize where the first batch of founders from the famous startup accelerator Y Combinator are now.

The Y Combinator startup directory includes every company YC has funded

The startup accelerator has funded more than 5,000 companies over the years. This YC-specific search engine lets you look up any company to find out if it's a YC alum.

87% of the startups in Y Combinator’s Fall 2025 batch were AI companies

Y Combinator also recently increased its number of cohorts or “batches” per year from two to four. Its leaders cited artificial intelligence’s rise as a reason for the increase.

Explore the schedule of a three-month YC batch

During the three months that founders accepted into Y Combinator spend on YC’s California campus, they receive mentorship from YC partners, networking opportunities, and, overall, a ton of time to build and scale their companies.

Watch the DoorDash team's YC application video

In 2013, the cofounders of DoorDash created a simple, homemade video application to Y Combinator. They didn't know it at the time, but they'd be accepted—and their company would go on to be publicly traded on the NASDAQ.

Mark Zuckerberg credits some of Facebook's success to constant evolution

Before becoming the head of OpenAI, Sam Altman was the president of Y Combinator—a startup accelerator company that supported companies like Airbnb, DoorDash, and Coinbase. In 2016, Altman interviewed Zuckerberg about creating Facebook and its growth over time. Zuckerberg said that, unlike other companies (think: CourseMatch), Facebook kept growing and adding new features, which prevented the app from becoming obsolete.

'Founder mode' is the idea that startup founders should take a hands-on approach to running their businesses

In 2024, Y Combinator cofounder Paul Graham popularized the idea of "founder mode" when he wrote a viral manifesto in response to a talk that Airbnb CEO Brian Chesky gave about leadership styles. Graham positioned the concept of founder mode as the opposite of manager mode—when founders hire executives and middle managers to run their companies and make decisions that Graham says are better left to founders.

Airbnb's Brian Chesky explains 'Founder Mode' and how he took back control

The short-term rental CEO learned hard lessons through the pandemic, specifically around a culture focused on management and not building products. In the fall of 2024, Chesky gave a well-received speech at a startup conference that prompted debate in the startup world. He summarizes the talk here.

Y Combinator has a roughly 1% acceptance rate

That’s lower than the most elite universities and colleges in the world—but insiders have some tips about how applicants can have the best shot of being accepted to the selective startup accelerator.

Watch a rare early interview with Palantir CEO Alex Karp

Prior to Palantir's public listing in 2020, CEO Alex Karp did not give many interviews. In a rare interview from 2009, Karp discussed the dominance of American technology, his academic background, and the founding idea of Silicon Valley entrepreneurs as key players in aiding the fight against terrorism.

'Founder mode' is the idea that founders should take a hands-on approach to running their businesses

In 2024, Y Combinator Cofounder Paul Graham wrote a viral manifesto of sorts about a strategy he calls "founder mode." It's the opposite of what Graham calls "manager mode," which allows founders to hire executives who he says ultimately run the company into the ground.

Apple CEO Tim Cook on what it takes to run the world's largest company

Apple CEO Tim Cook is a tough interview subject. He doesn't give many of them, and when he does it's often difficult to move him off of his talking points. In this interview for Dua Lipa's podcast, however, he opens up for a wide-ranging discussion about everything from artificial intelligence to the impact of technology on climate change—in addition to his own personal journey and his philanthropic endeavors.

TikTok CEO Shou Zi Chew on its future

TikTok CEO Shou Zi Chew dives into how the trendsetting video app and cultural phenomenon works, from what distinguishes its algorithm and drives viral videos, to the challenges of content moderation and digital addiction in this wide-ranging conversation with the head of TED, Chris Anderson.

‘Demo days’ are when founders at Y Combinator pitch their startup ideas

Investors sit in the audience, waiting to hear what this season’s batch of YC founders have cooked up. YC argues that going through the process of a demo day can help founders get a better understanding of their startup themselves.

Meet the investor running his life with AI

Daniel Ha is a venture capitalist who built a suite of AI agents to boost his productivity, both professionally and personally. At his VC firm, a troupe of agents gathers data on startups and analyzes it from competing perspectives to produce a confidence score. When his dad was diagnosed with cancer, Ha used an oncology-trained AI to help him understand the condition.

Anthropic's staff philosopher discusses the importance of teaching ethics to AI

Amanda Askell's work focuses on the behavior and values reflected in Claude, the company's AI chatbot, and how its character can better align with how the "ideal person" would act in Claude's position. She also emphasizes the importance of humans being ethical in their interactions with current models, from which future ones will be built.

For Reddit's founders, the company's early days included choosing a dinner with Y Combinator's Paul Graham over a spring break trip, a $10M Condé Nast acquisition, and other pivotal moments.

Sam Altman acknowledges the fears around creativity, copyright, and misuse of AI

In 2022, OpenAI's CEO, Sam Altman, popularized the use of large language models with the release of ChatGPT. He has emphasized the importance of involving society in shaping AI’s safety frameworks before models begin to act independently online.

Startup accelerators that include more training activities, such as pitch competitions, tend to have better long-term success rates

That's according to a new study from Wharton. Y-Combinator, perhaps the most famous startup accelerator, currently has 16 alumni companies trading on the public market. But not every entrepreneur who joins a startup accelerator makes it big.

A chat with YouTube CEO Neal Mohan

In a conversation with Bloomberg, YouTube CEO Neal Mohan maps out how the company is taking what it’s learned thus far and embedding itself into the “lean-back” TV viewing experience.

Listen to Palantir CEO Alex Karp's outlook for how AI will change the economy.

Read Sam Altman's life advice that he wrote in a blog post before he became CEO of OpenAI, from "don't lose touch with old friends" to "occasionally stay up until the sun rises talking to people."

Google’s CEO has warned that today’s AI boom shows ‘elements of irrationality’

An interview with Alphabet CEO Sundar Pichai warns that the trillion-dollar surge in AI valuations may contain clear signs of irrationality, echoing past tech bubbles. He says no firm—including Google—would be immune if the boom cools or bursts.

OpenAI helped kick-start an AI arms race in Silicon Valley

Led by CEO Sam Altman, OpenAI's mission is to "ensure artificial general intelligence benefits all of humanity" by making its products open to all users. In 2023, the $86B company behind the chatbot ChatGPT consisted of a for-profit arm under its nonprofit governing board.

Listen to a conversation between two Palantir cofounders—Peter Thiel and Joe Lonsdale

Palantir cofounder Joe Lonsdale was an editor of the Stanford Review (which Peter Thiel founded), and Thiel became a mentor to Lonsdale. The two discussed shared sentiments about the importance of developing Palantir to maintain a largely American global order, as well as cultural revolutions.