Refolk

Y Combinator portfolio AI companies

The most prolific seed accelerator in the world, batch class twice a year. Filtered to companies in AI.

Built from a search like: Y Combinator-backed AI companies

Ranked by current headcount across Y Combinator-backed AI companies. Refreshed daily.

  1. 1
    OpenAI· San Francisco, California, United States

    OpenAI is an AI research and deployment company dedicated to ensuring that general-purpose artificial intelligence benefits all of humanity. AI is an extremely powerful tool that must be created with safety and human needs at its core. OpenAI is dedicated to putting that alignment of interests first — ahead of profit.To achieve our mission, we must encompass and value the many different perspectives, voices, and experiences that form the full spectrum of humanity. Our investment in diversity, equity, and inclusion is ongoing, executed through a wide range of initiatives, and championed and supported by leadership.At OpenAI, we believe artificial intelligence has the potential to help people solve immense global challenges, and we want the upside of AI to be widely shared. Join us in shaping the future of technology.

    • Series unknown
    • 10.5k employees
    • Founded 2015
  2. 2
    BillionToOne· Menlo Park, California, United States

    BillionToOne is a precision diagnostics company with the mission to make molecular diagnostics more accurate, efficient, and accessible. Our proprietary molecular counting platform can accurately count DNA molecules at the single-count level to help improve disease detection.

    • Series D
    • 839 employees
    • Founded 2016
  3. 3
    Ginkgo Bioworks· Boston, Massachusetts, United States

    Ginkgo Bioworks builds the tools that make biology easier to engineer for everyone. We offer autonomous laboratories that replace manual laboratory work with robotics in the lab, greatly improving the productivity of scientists. Ginkgo's in-house autonomous lab is also available as a "cloud lab" through our Datapoints and Solutions contract research services.

    • Grant
    • 516 employees
    • Founded 2009
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  5. 4
    54gene· Nigeria

    54gene addresses the significant gap in the global genomics market; Nearly 90% of genetic material used in pharmaceutical research is Caucasian. Only 2% is African, despite the fact that Africans and people of African ancestry are more genetically diverse than all other world populations combined. As a result, pharmaceutical research and development is lacking the diverse data that may hold the key to medical discoveries and new healthcare solutions.

    • Convertible note
    • 114 employees
    • Founded 2019
  6. 5
    Nomic Bio· Montreal, Quebec, Canada

    Nomic was founded to make biology easier to measure and enable scientists to extend lives by making proteomics accessible, scalable, and routine. Powered by its proprietary nELISA® technology, Nomic delivers large-scale, quantitative, and cost-effective protein data to accelerate discovery, development, and translation. Its end-to-end service combines flexible content, expert support, and analysis-ready outputs—enabling seamless integration of proteomics across all stages of drug and biomarker development. Nomic’s mission is to make proteomics ubiquitous for modern biology.

    • Series B
    • 106 employees
    • Founded 2017

Y Combinator’s AI portfolio

The list above ranks Y Combinator-backed AI companies by current headcount, drawn from public LinkedIn and Crunchbase records. 139 matching companies in Refolk’s index give you a quick read on where Y Combinator has gone deepest in the AI space.

Y Combinator’s AI bets tend to share a thesis. The engineers, ML researchers, and founders inside these companies are often building the same primitives - and they show up in AI talent pools across the next decade.

Refolk converts this list into a live search. Ask for Y Combinator AI companies hiring senior engineers” or “founders of Y Combinator-backed AI companies” and Refolk returns a fresh ranked shortlist.

How this list is built

Refolk pulled AI companies whose disclosed Crunchbase investor list includes Y Combinator, ranked them by current employee count, and kept those with at least 5 employees. The list refreshes once a day.

Last refreshed: Wed, 05 Aug 2026 16:02:29 GMT

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How is this ranking built?

The list draws on the public company graph - headcount and growth signals, funding history, and recency. The criteria chips at the top show exactly which filters produced it, and the methodology section explains the ranking.

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The underlying index updates continuously and this page re-renders at least daily. Last refreshed: Wed, 05 Aug 2026 16:02:29 GMT.

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