HomeCompaniesNapkin Math
Napkin Math

the hyper-The hyper-personalized AI food journal that helps people…

Existing consumer health apps focus on scaling a one-size-fits-all solution: calorie deficits. But they don’t answer the questions you actually have. Food is deeply personal, and so is Napkin Math: Get the fuel you need for marathon training, while understanding you eat catered office lunches five days a week. Discover what’s triggering your stomach irritation, without sacrificing your weekly dinner with friends. Napkin Math tailors a plan for not only your specific health goal, but also your life.
Active Founders
Manuel Castro
Manuel Castro
Founder
Napkin Math is the hyper-personalized AI food journal that helps people achieve their health goals. Previously: Sonos, Healthcare Tech, Verkada
Claire Nord
Claire Nord
Founder
Building Napkin Math, hyper-personalized AI food journal https://napkinmath.club Prev. Apple OS security, Samsara, MIT 6-3 '19
Jynnie Tang
Jynnie Tang
Founder
Making Napkin Math, the personalized AI food journal that helps people achieve their health goals Previously: Retool, One More Multiverse, MIT
Company Launches
Napkin Math - hyper-personalized AI food journal
See original launch post

TL;DR: Napkin Math is the hyper-personalized AI food journal that helps people achieve their health goals.

Join at https://napkinmath.club 🧺

https://youtu.be/IJ09vrOkSOE

THE PROBLEM & THE PRODUCT

Existing consumer health apps focus on scaling a one-size-fits-all solution: calorie deficits. But they don’t answer the questions you actually have.

Food is deeply personal, and so is Napkin Math:

  • Get the fuel you need for marathon training, while understanding you eat catered office lunches five days a week
  • Discover what’s triggering your stomach irritation, without sacrificing your weekly dinner with friends.

Napkin Math tailors a plan for not only your specific health goal, but also your life.

uploaded image

THE KEY INSIGHTS

Why hasn’t this been done before?

  1. Before AI, personalization was impossible. Tailoring a plan to every chronic condition, allergy, goal, and stage of life was impossible. With frontier models, we’re able to reimagine nutrition experiences from the ground up.
  2. We understand how to make taking a picture of your food fun. How come Instagram foodies, who religiously follow “the camera eats first”, don’t also log their food in a journal? Napkin Math perfectly marries the joy of socially sharing food with a rich database that can help foodies feel better every day.

THE TEAM

We’ve been friends for a decade since living together at MIT. 🧑‍🧑‍🧒

Jynnie worked on a games platform with 1MM players (Multiverse YC W20) and one of the largest Discord Games (Magic Circle, a16z Speedrun) — applying real gamification experience with AI to consumer health.

Manuel has cracked product across consumer, healthcare, and hardware, recently leading Verkada’s largest product line — bringing AI to real problems.

Claire’s work at Samsara through its IPO has given her insight into how tracking leads to safety outcomes for drivers, and now health outcomes for Napkin Math users.

Happy Tummy, Happy Life 😉 Try Napkin Math

YC Photos
Napkin Math
Founded:2026
Batch:Spring 2026
Team Size:3
Status:
Active
Location:San Francisco
Primary Partner:Pete Koomen