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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 monthly.

  1. 1
    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
    • 849 employees
    • Founded 2016
  2. 2
    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
    • 505 employees
    • Founded 2009
  3. 3
    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
    • 112 employees
    • Founded 2019
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  5. 4
    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
    • 107 employees
    • Founded 2017
  6. 5
    Ansa Biotechnologies, Inc.· Emeryville, California, United States

    At Ansa Biotechnologies, we’re developing a way to synthesize DNA that will accelerate innovation in medicine, agriculture, and industrial biotechnology. Our fast, clean, and accurate enzymatic DNA synthesis process can produce gene-length molecules directly, overcoming bottlenecks of traditional DNA synthesis methods. We envision a future where our technology empowers scientists to develop solutions for the world's biggest problems in health and sustainability.Note that Ansa does not conduct any employment discussions via LinkedIn. All official Ansa career openings are exclusively listed on our website careers page.

    • Series B
    • 81 employees
    • Founded 2018

Y Combinator’s AI portfolio

The list above ranks Y Combinator-backed AI companies by current headcount, drawn from public LinkedIn and Crunchbase records. 136 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 monthly.

Last refreshed: Sun, 13 Sep 2026 22:34:25 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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