Y Combinator

Y Combinator co-founder Jessica Livingston on the beginnings of YC.

Jessica Livingston, Gary

Established in 2005 Boston, this venture capitalized on a capital-starved market to create a dedicated early-stage vehicle addressing the scarcity of small seed funds. The entity launched a distinct strategy of issuing modest checks specifically to provide founders with the liquidity needed to quit their jobs and validate ideas before pursuing larger funding rounds. This approach successfully filled a critical gap in the angel investment landscape by bridging the gap between untested concepts and traditional venture capital requirements.

New Defense Technology

Amidst concerns that bloated defense contractors are hindering U.S. technological leadership, Y Combinator is actively recruiting startups to emulate agile innovators like Palantir and SpaceX. This strategic initiative leverages Silicon Valley's historical roots as a military R&D hub, a legacy physically embodied by the Y Combinator headquarters which formerly operated as a World War II naval shipbuilding facility. With the next decade framed as a critical window for reinvigorating defense capabilities, the program seeks to catalyze a new wave of defense-oriented companies in San Francisco.

How To Convert Customers With Cold Emails | Startup School

Aaron Epstein

This event details a data-driven outreach framework where founders must personally execute high-volume email campaigns using warm introductions or targeted cold strategies to secure B2B customers. The speaker outlines a specific funnel architecture that requires sending dozens of daily messages while applying seven principles of effective copy, such as humanized tone, deep personalization, and clear calls to action, to maximize response rates. By analyzing case studies of both failed and successful campaigns, the presentation emphasizes that manual, founder-led execution is essential for building initial traction before any automation is introduced.

How YC Was Created With Jessica Livingston

Jessica Livingston, Harj, Yuri Milner, Diana, Gary, Jared

Founded in 2005 by Jessica Livingston and Paul Graham, Y Combinator pioneered the mass-production of startups by replacing traditional venture capital barriers with standardized legal deals and a "batch" model that fostered intense peer collaboration. The organization evolved from providing $10,000 checks to distributing millions per cohort, a shift catalyzed by investor Yuri Milner and proven through massive returns from companies like Reddit, Airbnb, and Dropbox. By prioritizing unconventional founders and maintaining an earnest, non-commercial culture, Y Combinator transformed early-stage funding into a global ecosystem where community and rapid iteration supersede traditional business plans.

Over-complicated pricing could kill a sales process.

This analysis recommends prioritizing simple, committed recurring revenue models like Monthly or Annual Recurring Revenue over complex or usage-based structures. Advocates argue that committed contracts protect revenue during economic downturns and align better with investor expectations by preventing immediate income collapse. Consequently, the strategic goal is to target MRR or ARR to ensure stability and facilitate value-based renewal negotiations.

We’re still in the early innings with AI.

YC-backed ventures like DoorDash, Instacart, and Uber exemplify smartphone-driven success stories that launched roughly four years after the iPhone's release. These examples demonstrate that determining which ideas will succeed and where value will accumulate requires a significant period of maturation before market dominance can be achieved.

How To Keep Your Users | Startup School

David Lieb

YC Group Partner David Leib leverages his experience scaling Bump and Google Photos to argue that high cohort retention is the definitive quantitative signal of product-market fit. He details precise methodologies for defining user actions, selecting appropriate measurement intervals, and interpreting retention curve shapes to distinguish sustainable growth from a churn-heavy treadmill. By avoiding common analytical pitfalls and applying strategies like user acquisition targeting and onboarding optimization, founders can transform cohort data into a actionable roadmap for building scalable, long-term businesses.

Gmail creator Paul Buchheit on the very first version of Google’s “Did you mean?” feature

Paul Buchheit

A former Google engineer designed the original "Did you mean" spell correction feature after analyzing query logs that revealed roughly one-third of searches contained errors. Although the initial implementation used a standard spell correction library, it frequently produced incorrect suggestions, such as recommending the fish "Turbot" for "TurboTax." These early accuracy failures highlighted the complexity of auto-correction and drove subsequent refinements to the system's reliability.

Sales pre-PMF should be done by the founders.

Early-stage B2B startup founders must personally drive sales efforts prior to achieving product-market fit to validate their business models effectively. Because this pre-PMF selling requires entrepreneurial vision and a tight feedback loop with product development, external sales hires often fail to replicate these critical dynamics. Relying on external sales teams before validation is identified as a suboptimal strategy that risks the venture's ability to succeed later.

Are We In An AI Hype Cycle?

Gary, Jared, Harj, Diana, Mark Mandelmann, Jr., Melanie Warrick, Mark Mandelbacher

Y Combinator is launching its first-ever Fall batch, offering $500,000 in funding with an application deadline of August 27th. The organization analyzes the current AI market through a dual lens of heightened hype cycles and tangible application-layer utility, contrasting speculative valuations against revenue-generating tools that demonstrate clear enterprise efficiency. While acknowledging risks of overinvestment similar to past tech bubbles, YC emphasizes that long-term value will accrue to companies solving specific customer problems rather than relying on foundation model speculation.

How Nothing Founder Carl Pei Built A Multi-Million Dollar Smartphone Brand In Just 2 Years

Carl Pei

Nothing founder Carl Pei details the company's strategic pivot from a bankrupt partnership with a Chinese factory to achieving $600 million in annualized revenue by overcoming a 90% return rate on its "ear one" product. Pei advocates for hardware founders to prioritize operational stability over design innovation, utilizing a "two-second rule" for features like the Glyph Interface to mitigate screen addiction and build brand trust. This approach enabled the startup to successfully validate its supply chain with 600,000 units sold and establish a foundation for future smartphone ambitions in the highly competitive hardware sector.

Gmail Creator Paul Buchheit On AGI, Open Source Models, Freedom

Paul Buchheit, Jared, Harj, Diana, Noam Shazier, Mark Mandelbaum, Mark Blyth, Paul Lewisohn, Zuck Meyer, Melanie Warrick, Gary Illyes, Lyn Alden

Paul Buchheit and Noam Shazier trace Google's evolution from an AI-first innovator to a risk-averse monopoly that stifled tools like Lambda to protect search revenue, while OpenAI emerged as a non-profit counter-movement funded by figures like Elon Musk to keep research open. Buchheit champions open-source models as essential for preserving individual liberty against Big Tech centralization and authoritarian surveillance, predicting that algorithmic efficiency will soon lower barriers for small teams to build AGI. He warns that regulatory overreach like SB 1047 will force excessive censorship and that the future workforce will face displacement by autonomous AI agents capable of deep-faking knowledge work by 2033.

How To Price For B2B | Startup School

Tom Blomfield

Founders are advised to anchor pricing in a collaborative value equation that quantifies customer ROI, setting rates between 25% and 50% of that value to ensure healthy margins while retaining two-thirds of the benefit for the client. The strategy explicitly discourages cost-plus or predatory price wars, instead urging a shift toward recurring revenue models and short, metric-driven pilots to mitigate revenue volatility. By treating cloud credits as real costs and avoiding public price transparency for enterprise deals, this framework enables startups to secure sustainable growth without triggering a race to the bottom.

Tarpit Ideas: The Sequel

Dalton, Michael

YC partners Dalton and Michael define "tar pit" ideas as market spaces that appear highly attractive but historically fail due to a lack of genuine technological shifts or fundamental behavioral changes. While Large Language Models have rendered some previously impossible ventures viable, founders must demonstrate concrete problem-solving capabilities rather than relying on social validation or assuming the first successful iteration is imminent. This dynamic framework warns against behavioral coordination failures and fast wealth arbitrage, urging entrepreneurs to rigorously validate ideas against historical precedents and actual user needs.

Why Startup Founders Should Launch Companies Sooner Than They Think

This presentation dismantles the myth of the single-shot launch, arguing that founders should immediately release imperfect MVPs to gather critical data rather than delaying for perfection. It highlights Y Combinator's peer-pressure strategy and case studies like Airbnb and Brex to demonstrate that early failure provides essential learning while the market rarely remembers product stumbles. By redefining launch goals from revenue generation to information gathering, founders can overcome psychological barriers to build products that deeply serve a small, urgent user base.