Product Market Fit

Product Market Fit

Startup Playbooks

YC Just Told Founders Where to Build

The Categories YC’s Own Batch Data Says Are Wide Open Right Now

Guillermo Flor's avatar
Guillermo Flor
Sep 21, 2026
∙ Paid

Garry Tan, Jared Friedman, Diana Hu and Harj Taggar went through the batch-level data on every company accepted in the last eighteen months: which sectors grew, by how much, which ones are producing revenue in weeks and what kind of founder is winning inside each one.

  • A fifth of the batch has moved into atoms

  • A quarter is building agents that do an entire job on their own

  • A layer of suppliers almost nobody talks about is selling training data to the frontier labs at eight and nine figures

  • And the founders outperforming everyone are solo operators in their forties and fifties

Below is the full build list: the categories, the number YC disclosed for each one, and what each one asks of you if you decide to go after it.


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In this guide you’ll find:

  1. Start With Atoms

    Hard Tech Went From 8% to 20% of the Batch

  2. Why You Can Afford to Build Hardware Now

    Codegen Removed the Thousand-Engineer Requirement

  3. Sell to the Buyers Nobody Is Serving

    Defense Contracts and Detroit Manufacturing

  4. Build the Picks and Shovels of Compute

    Sites, Power, Silicon and the Switch Bottleneck

  5. Get Into Robotics Before the ChatGPT Moment

    The Benchmark Jumped From 10% to 70%

  6. Own the Footage Your Robot Learns From

    Why Every YC Robotics Company Fine-Tunes

  7. Build the Place Where the Work Happens

    Why Salesforce Grew While Everyone Called SaaS Dead

  8. Build Agents That Do the Whole Job

    The Path From Zero to Seven Figures in Three Months

  9. Sell to the Labs

    Data and RL Environments Are a Nine-Figure Category

  10. Go Solo If You Have Been Around the Block

    Solo Founders Tripled to 19%


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