Y Combinator portfolio AI companies

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

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

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

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
- 10.7k employees
- Founded 2015
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
- 846 employees
- Founded 2016
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
- 499 employees
- Founded 2008
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4
Opentrons Labworks Inc.· Long Island City, New York, United States
Opentrons Labworks, Inc., is a disruptive life science company leveraging its integrated lab platform to supercharge the pace of innovation in research and healthcare. Opentrons Labworks is the parent company to business units Opentrons Robotics and Neochromosome. Through Opentrons Robotics, thousands of institutions are automating R&D operations with flexible, easy-to-use liquid handling lab robots. Through Neochromosome, biopharma and biotech at large can benefit from our world-class genome-scale cell engineering solutions. Opentrons Robotics, a business unit of Opentrons Labworks, Inc., is the industry leader in flexible, user-friendly automation for life science labs. Our open-source ecosystem offers the scientific community the tools they need to automate experiments, share protocols and reproduce each other's results. Opentrons robots can be found in thousands of academic, biopharma, synthetic biology and clinical research labs in more than 40 countries.
- Series D
- 194 employees
- Founded 2014
5
54gene· Lagos, 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

6
Nomic Bio· Plateau Mont-Royal West, Québec, 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
- 108 employees
- Founded 2017
7
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
8
Metis (Acquired by DoorDash)· San Francisco, California, United States
We build infrastructure enabling AI agents to reliably perform complex digital work tasks.
- Pre-seed
- 77 employees
- Founded 2025
9
Miracle· San Francisco, California, United States
Pulling your hair out in clinical trials because of spreadsheet madness?You’re not alone. Most biotech teams lose weeks, if not months, to manual spreadsheet trackers, delayed insights, and inadequate vendor oversight.That’s exactly why we built Miracle.👉 Speed: Replace clunky manual trackers with an integrated platform that gets you live in just days (not weeks or months).👉 Clarity: Real-time visibility across trials, so your execs stop asking you for “one quick update” every day.👉 Proof: Clinical-stage biotechs using Miracle have already finished 3-4 months ahead of trial timelines, freeing their teams from spreadsheet hell and resolving risks as soon as they occur, not next week.If you’re a biotech exec staring down another delayed trial (or want to start your study on the right foot), Miracle can help you close the gap.📩 Message us here or reach out at https://www.miracleml.com/contactLet’s make “trial delays” something you don’t talk about next quarter.
- Seed
- 75 employees
- Founded 2022
10
Planet A Foods· Krailling, Planegg, Bavaria, Germany
Imagine a world without chocolate. Horrifying, right? But the supply of cocoa is endangered and chocolate is as bad as meat for our planet.We make future-proof chocolate using precision fermentation. Doing this, our chocolate is 10x more sustainable and 20% cheaper than conventional chocolate. In order to mimic the organoleptic properties of chocolate (tender, smoothly melting taste release) we are working on the flavor itself but also on replacing the cocoa butter.55 Mio lbs of chocolate are consumed every day. By 2035 we will substitute a big chunk of it through our sustainable chocolate.
- Corporate
- 74 employees
- Founded 2021

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Y Combinator’s AI portfolio

The list above ranks Y Combinator-backed AI companies by current headcount, drawn from public LinkedIn and Crunchbase records. 145 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: Wed, 14 Oct 2026 04:04:24 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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